README: fixed URLs.

Author: igorsysoev

README.md

@@ -205,7 +205,7 @@ current working directory.
 ##### Tarball
 
 Unit source code tarballs are available at
-<http://unit.nginx.org/download/>
+[http://unit.nginx.org/download/](http://unit.nginx.org/download/)
 
 #### Installing Required Software
 
@@ -882,9 +882,10 @@ All other requests will be proxied to Unit:
 }
 ```
 
-Refer to NGINX documentation at <http://nginx.org> for more information.
+Refer to NGINX documentation at [http://nginx.org](http://nginx.org)
+for more information.
 Commercial support and advanced features are available at
-<https://www.nginx.com>
+[https://www.nginx.com](https://www.nginx.com)
 
 ### Securing and Proxying Unit API
 
@@ -932,8 +933,9 @@ server {
 
 NGINX Unit is released under the Apache 2.0 license.
 
-To contribute changes, either submit them by email to <[email protected]> or
-submit a pull request in the <https://github.com/nginx/unit> repository.
+To contribute changes, either submit them by email to
+[[email protected]](mailto:[email protected]) or submit a pull request in the
+[https://github.com/nginx/unit](https://github.com/nginx/unit) repository.
 
 <!-- /section:5 -->
 
@@ -956,7 +958,8 @@ Unit and all modules have to be recompiled and reinstalled after reconfiguring.
 Please be aware that the debug log size grows very quickly.
 
 Community mailing list is available at <[email protected]>.
-Subscribe to the mailing list by sending email to <[email protected]> or
-at <http://mailman.nginx.org/mailman/listinfo/unit>.
+Subscribe to the mailing list by sending email to
+[[email protected]](mailto:[email protected])
+or at [here](http://mailman.nginx.org/mailman/listinfo/unit).
 
 <!-- /section:6 -->