Sync bob docs with problem-specifications (#278)

The bob exercise has been overhauled as part of a project
to make practice exercises more consistent and friendly.

For more context, please see the discussion in the forum, as well as
the pull request that updated the exercise in the problem-specifications
repository:

- https://forum.exercism.org/t/new-project-making-practice-exercises-more-consistent-and-human-across-exercism/3943
- exercism/problem-specifications#2205

Author: kytrinyx

exercises/practice/bob/.docs/instructions.md

@@ -1,16 +1,19 @@
 # Instructions
 
-Bob is a lackadaisical teenager.
-In conversation, his responses are very limited.
+Your task is to determine what Bob will reply to someone when they say something to him or ask him a question.
 
-Bob answers 'Sure.' if you ask him a question, such as "How are you?".
+Bob only ever answers one of five things:
 
-He answers 'Whoa, chill out!' if you YELL AT HIM (in all capitals).
-
-He answers 'Calm down, I know what I'm doing!' if you yell a question at him.
-
-He says 'Fine. Be that way!' if you address him without actually saying anything.
-
-He answers 'Whatever.' to anything else.
-
-Bob's conversational partner is a purist when it comes to written communication and always follows normal rules regarding sentence punctuation in English.
+- **"Sure."**
+  This is his response if you ask him a question, such as "How are you?"
+  The convention used for questions is that it ends with a question mark.
+- **"Whoa, chill out!"**
+  This is his answer if you YELL AT HIM.
+  The convention used for yelling is ALL CAPITAL LETTERS.
+- **"Calm down, I know what I'm doing!"**
+  This is what he says if you yell a question at him.
+- **"Fine. Be that way!"**
+  This is how he responds to silence.
+  The convention used for silence is nothing, or various combinations of whitespace characters.
+- **"Whatever."**
+  This is what he answers to anything else.

exercises/practice/bob/.docs/introduction.md

@@ -0,0 +1,10 @@
+# Introduction
+
+Bob is a [lackadaisical][] teenager.
+He likes to think that he's very cool.
+And he definitely doesn't get excited about things.
+That wouldn't be cool.
+
+When people talk to him, his responses are pretty limited.
+
+[lackadaisical]: https://www.collinsdictionary.com/dictionary/english/lackadaisical