minor #4042 [Cookbook] apply headline guidelines to the cookbook articles (xabbuh)

This PR was merged into the 2.3 branch.

Discussion
----------

[Cookbook] apply headline guidelines to the cookbook articles

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets |

This completes the work started in #3765, #3828 and #3829.

Commits
-------

1fa40f3 apply headline guidelines to the cookbook articles

Author: weaverryan

cookbook/assetic/apply_to_option.rst

@@ -1,7 +1,7 @@
 .. index::
    single: Assetic; Apply filters
 
-How to Apply an Assetic Filter to a Specific File Extension
+How to Apply an Assetic Filter to a specific File Extension
 ===========================================================
 
 Assetic filters can be applied to individual files, groups of files or even,
@@ -49,7 +49,7 @@ An example configuration might look like this:
             ),
         ));
 
-Filter a Single File
+Filter a single File
 --------------------
 
 You can now serve up a single CoffeeScript file as JavaScript from within your
@@ -75,7 +75,7 @@ templates:
 This is all that's needed to compile this CoffeeScript file and serve it
 as the compiled JavaScript.
 
-Filter Multiple Files
+Filter multiple Files
 ---------------------
 
 You can also combine multiple CoffeeScript files into a single output file:
@@ -107,7 +107,7 @@ JavaScript.
 
 .. _cookbook-assetic-apply-to:
 
-Filtering based on a File Extension
+Filtering Based on a File Extension
 -----------------------------------
 
 One of the great advantages of using Assetic is reducing the number of asset
@@ -146,7 +146,7 @@ applied to all ``.coffee`` files:
                 apply_to="\.coffee$" />
                 <assetic:node-paths>/usr/lib/node_modules/</assetic:node-path>
         </assetic:config>
-        
+
     .. code-block:: php
 
         // app/config/config.php

cookbook/assetic/asset_management.rst

@@ -159,7 +159,7 @@ the :ref:`cssrewrite <cookbook-assetic-cssrewrite>` filter.
 
 .. _cookbook-assetic-including-image:
 
-Including images
+Including Images
 ~~~~~~~~~~~~~~~~
 
 To include an image you can use the ``image`` tag.
@@ -422,7 +422,7 @@ into your template:
 A more detailed guide about configuring and using Assetic filters as well as
 details of Assetic's debug mode can be found in :doc:`/cookbook/assetic/uglifyjs`.
 
-Controlling the URL used
+Controlling the URL Used
 ------------------------
 
 If you wish to, you can control the URLs that Assetic produces. This is
@@ -471,7 +471,7 @@ it might be downright frustrating.
 Fortunately, Assetic provides a way to dump your assets to real files, instead
 of being generated dynamically.
 
-Dumping Asset Files in the ``prod`` environment
+Dumping Asset Files in the ``prod`` Environment
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 In the ``prod`` environment, your JS and CSS files are represented by a single
@@ -500,7 +500,7 @@ This will physically generate and write each file that you need (e.g. ``/js/abcd
 If you update any of your assets, you'll need to run this again to regenerate
 the file.
 
-Dumping Asset Files in the ``dev`` environment
+Dumping Asset Files in the ``dev`` Environment
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 By default, each asset path generated in the ``dev`` environment is handled

cookbook/assetic/jpeg_optimize.rst

@@ -1,7 +1,7 @@
 .. index::
    single: Assetic; Image optimization
 
-How to Use Assetic For Image Optimization with Twig Functions
+How to Use Assetic for Image Optimization with Twig Functions
 =============================================================
 
 Amongst its many filters, Assetic has four filters which can be used for on-the-fly
@@ -111,7 +111,7 @@ remove these by using the ``strip_all`` option:
             ),
         ));
 
-Lowering Maximum Quality
+Lowering maximum Quality
 ~~~~~~~~~~~~~~~~~~~~~~~~
 
 The quality level of the JPEG is not affected by default. You can gain
@@ -152,7 +152,7 @@ image quality:
             ),
         ));
 
-Shorter syntax: Twig Function
+Shorter Syntax: Twig Function
 -----------------------------
 
 If you're using Twig, it's possible to achieve all of this with a shorter

cookbook/assetic/uglifyjs.rst

@@ -1,7 +1,7 @@
 .. index::
    single: Assetic; UglifyJS
 
-How to Minify CSS/JS Files (using UglifyJS and UglifyCSS)
+How to Minify CSS/JS Files (Using UglifyJS and UglifyCSS)
 =========================================================
 
 `UglifyJS`_ is a JavaScript parser/compressor/beautifier toolkit. It can be used
@@ -183,7 +183,7 @@ and :ref:`dump your assetic assets <cookbook-asetic-dump-prod>`.
     rather than the common config file. For details on applying filters by
     file extension, see :ref:`cookbook-assetic-apply-to`.
 
-Install, configure and use UglifyCSS
+Install, Configure and Use UglifyCSS
 ------------------------------------
 
 The usage of UglifyCSS works the same way as UglifyJS. First, make sure

cookbook/bundles/best_practices.rst

@@ -1,7 +1,7 @@
 .. index::
    single: Bundle; Best practices
 
-How to use Best Practices for Structuring Bundles
+How to Use best Practices for Structuring Bundles
 =================================================
 
 A bundle is a directory that has a well-defined structure and can host anything

cookbook/bundles/extension.rst

@@ -2,7 +2,7 @@
    single: Configuration; Semantic
    single: Bundle; Extension configuration
 
-How to expose a Semantic Configuration for a Bundle
+How to Expose a semantic Configuration for a Bundle
 ===================================================
 
 If you open your application configuration file (usually ``app/config/config.yml``),
@@ -330,7 +330,7 @@ information loaded from other bundles). The goal of the ``load()`` method
 is to manipulate the container, adding and configuring any methods or services
 needed by your bundle.
 
-Loading External Configuration Resources
+Loading external Configuration Resources
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 One common thing to do is to load an external configuration file that may
@@ -549,7 +549,7 @@ normalization and advanced merging. You can read more about this in
 You can also see it in action by checking out some of the core Configuration classes,
 such as the one from the `FrameworkBundle Configuration`_ or the `TwigBundle Configuration`_.
 
-Modifying the configuration of another Bundle
+Modifying the Configuration of another Bundle
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 If you have multiple bundles that depend on each other, it may be useful

cookbook/bundles/inheritance.rst

@@ -1,7 +1,7 @@
 .. index::
    single: Bundle; Inheritance
 
-How to use Bundle Inheritance to Override parts of a Bundle
+How to Use Bundle Inheritance to Override Parts of a Bundle
 ===========================================================
 
 When working with third-party bundles, you'll probably come across a situation

cookbook/bundles/installation.rst

@@ -1,7 +1,7 @@
 .. index::
    single: Bundle; Installation
 
-How to install 3rd party Bundles
+How to Install 3rd Party Bundles
 ================================
 
 Most bundles provide their own installation instructions. However, the

cookbook/bundles/override.rst

@@ -93,7 +93,7 @@ See :doc:`/cookbook/service_container/compiler_passes` for information on how to
 compiler passes. If you want to do something beyond just overriding the class -
 like adding a method call - you can only use the compiler pass method.
 
-Entities & Entity mapping
+Entities & Entity Mapping
 -------------------------
 
 Due to the way Doctrine works, it is not possible to override entity mapping
@@ -119,7 +119,7 @@ rather than::
 
 .. _override-validation:
 
-Validation metadata
+Validation Metadata
 -------------------
 
 Symfony loads all validation configuration files from every bundle and

cookbook/bundles/prepend_extension.rst

@@ -2,7 +2,7 @@
    single: Configuration; Semantic
    single: Bundle; Extension configuration
 
-How to simplify configuration of multiple Bundles
+How to Simplify Configuration of multiple Bundles
 =================================================
 
 When building reusable and extensible applications, developers are often