Remove s warning

Closes #51.

plugin/surround.vim

@@ -557,9 +557,6 @@ if !exists("g:surround_no_mappings") || ! g:surround_no_mappings
   nmap ySS <Plug>YSsurround
   xmap S   <Plug>VSurround
   xmap gS  <Plug>VgSurround
-  if maparg('s', 'x') ==# ''
-    xnoremap <silent> s :<C-U>echoerr 'surround.vim: Visual mode s has been removed in favor of S'<CR>
-  endif
   if !hasmapto("<Plug>Isurround","i") && "" == mapcheck("<C-S>","i")
     imap    <C-S> <Plug>Isurround
   endif