[clang] [clang][www] Documentation revision and proof read for features.html (PR #156620)

[via cfe-commits]

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@@ -183,7 +183,7 @@ <h3><a name="libraryarch">Library Based Architecture</a></h3>
     levels.</li>
 </ul>
 
-<p>As an example of the power of this library based design....  If you wanted to
+<p>As some examples for the power of this library based design: If you wanted to
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lknknm wrote:

Yes, mostly I just wanted to replace one of the `of` with another term/word to avoid repetition "of the... of this", but I think overall it's fine, I'll go with your suggestion as "Some examples of the power of this library based design are:"

https://github.com/llvm/llvm-project/pull/156620