Auto merge of #3032 - micbou:msvc-12-docs, r=micbou

[READY] Remove Visual Studio 12 generator from the docs

Forgot to remove this CMake generator in commit https://github.com/Valloric/YouCompleteMe/commit/9392f7fd6143344b4c2e1d3bbc2dc0257e3b4e87.

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README.md

@@ -654,7 +654,6 @@ process.
     where `<generator>` is `Unix Makefiles` on Unix systems and one of the
     following Visual Studio generators on Windows:
 
-    - `Visual Studio 12 Win64`
     - `Visual Studio 14 Win64`
     - `Visual Studio 15 Win64`
 

doc/youcompleteme.txt

@@ -884,7 +884,6 @@ will notify you to recompile it. You should then rerun the install process.
    where '<generator>' is 'Unix Makefiles' on Unix systems and one of the
    following Visual Studio generators on Windows:
 
-   - 'Visual Studio 12 Win64'
    - 'Visual Studio 14 Win64'
    - 'Visual Studio 15 Win64'