Silence any perl warnings

Closes #107.

Author: tpope

autoload/dispatch.vim

@@ -101,7 +101,7 @@ endfunction
 function! dispatch#prepare_start(request, ...) abort
   let exec = 'echo $$ > ' . a:request.file . '.pid; '
   if executable('perl')
-    let exec .= 'perl -e "select(undef,undef,undef,0.1)"; '
+    let exec .= 'perl -e "select(undef,undef,undef,0.1)" 2>/dev/null; '
   else
     let exec .= 'sleep 1; '
   endif