Auto merge of #2924 - micbou:capture-vim-command-unicode, r=puremourning

[READY] Convert Vim command output to Unicode

Forgot to do that in PR https://github.com/Valloric/YouCompleteMe/pull/2921.

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python/ycm/vimsupport.py

@@ -175,7 +175,7 @@ def CaptureVimCommand( command ):
   vim.command( 'redir => b:ycm_command' )
   vim.command( 'silent! {}'.format( command ) )
   vim.command( 'redir END' )
-  output = vim.eval( 'b:ycm_command' )
+  output = ToUnicode( vim.eval( 'b:ycm_command' ) )
   vim.command( 'unlet b:ycm_command' )
   return output