Merge https://github.com/Valloric/YouCompleteMe

autoload/youcompleteme.vim

@@ -164,7 +164,7 @@ endfunction
 
 
 function! s:AllowedToCompleteInCurrentFile()
-  if empty( &filetype )
+  if empty( &filetype ) || getbufvar(winbufnr(winnr()), "&buftype") ==# 'nofile'
     return 0
   endif
 

python/ycm/completers/cs/cs_completer.py

@@ -34,7 +34,7 @@ import tempfile
 
 SERVER_NOT_FOUND_MSG = ( 'OmniSharp server binary not found at {0}. ' +
 'Did you compile it? You can do so by running ' +
-'"./install.sh --omnisharp_completer".' )
+'"./install.sh --omnisharp-completer".' )
 
 class CsharpCompleter( ThreadedCompleter ):
   """