Clearer wording on the YCM warning (SirVer#1244)

Co-authored-by: Florian Westreicher <[email protected]>

README.md

@@ -44,7 +44,7 @@ for your plugin manager of choice. Put this into your `.vimrc`.
     " Snippets are separated from the engine. Add this if you want them:
     Plugin 'honza/vim-snippets'
 
-    " Trigger configuration. Do not use <tab> if you use https://github.com/Valloric/YouCompleteMe.
+    " Trigger configuration. You need to change this to something else than <tab> if you use https://github.com/Valloric/YouCompleteMe.
     let g:UltiSnipsExpandTrigger="<tab>"
     let g:UltiSnipsJumpForwardTrigger="<c-b>"
     let g:UltiSnipsJumpBackwardTrigger="<c-z>"