Auto merge of #2344 - micbou:documentation-semantic-completion-other-languages, r=Valloric

[READY] Mention all natively supported languages in documentation

We mention all supported languages except C-family languages and JavaScript in the `Semantic Completion for Other Languages` section of the documentation. Add them.

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README.md

@@ -977,15 +977,16 @@ package you have in the virtual environment.
 
 ### Semantic Completion for Other Languages
 
-Python, C#, Go, Rust, and TypeScript are supported natively by YouCompleteMe
-using the [Jedi][], [Omnisharp][], [Gocode][], [racer][], and [TSServer][]
-engines, respectively. Check the [installation](#installation) section for
-instructions to enable these features if desired.
+C-family, C#, Go, JavaScript, Python, Rust, and TypeScript languages are
+supported natively by YouCompleteMe using the [Clang][], [OmniSharp][],
+[Gocode][]/[Godef][], [Tern][], [Jedi][], [racer][], and [TSServer][] engines,
+respectively. Check the [installation](#installation) section for instructions
+to enable these features if desired.
 
 YCM will use your `omnifunc` (see `:h omnifunc` in Vim) as a source for semantic
 completions if it does not have a native semantic completion engine for your
 file's filetype. Vim comes with okayish omnifuncs for various languages like
-Ruby, PHP etc. It depends on the language.
+Ruby, PHP, etc. It depends on the language.
 
 You can get stellar omnifuncs for Java and Ruby with [Eclim][]. Just make sure
 you have the _latest_ Eclim installed and configured (this means Eclim `>= 2.2.*`

doc/youcompleteme.txt

@@ -1229,15 +1229,16 @@ package you have in the virtual environment.
                         *youcompleteme-semantic-completion-for-other-languages*
 Semantic Completion for Other Languages ~
 
-Python, C#, Go, Rust, and TypeScript are supported natively by YouCompleteMe
-using the Jedi [6], Omnisharp [8], Gocode [9], racer [13], and TSServer [11]
-engines, respectively. Check the installation section for instructions to
-enable these features if desired.
+C-family, C#, Go, JavaScript, Python, Rust, and TypeScript languages are
+supported natively by YouCompleteMe using the Clang [5], OmniSharp [8], Gocode
+[9]/Godef [10], Tern [12], Jedi [6], racer [13], and TSServer [11] engines,
+respectively. Check the installation section for instructions to enable these
+features if desired.
 
 YCM will use your 'omnifunc' (see ':h omnifunc' in Vim) as a source for
 semantic completions if it does not have a native semantic completion engine
 for your file's filetype. Vim comes with okayish omnifuncs for various
-languages like Ruby, PHP etc. It depends on the language.
+languages like Ruby, PHP, etc. It depends on the language.
 
 You can get stellar omnifuncs for Java and Ruby with Eclim [48]. Just make sure
 you have the _latest_ Eclim installed and configured (this means Eclim '>=