Add repeat.vim support to surround with LaTeX environment 'ys<>l'

plugin/surround.vim

@@ -212,10 +212,11 @@ function! s:wrap(string,char,type,removed,special)
   elseif newchar ==# 'l' || newchar == '\'
     " LaTeX
     let env = input('\begin{')
+    if env != ""
+      let s:input = env."\<CR>"
       let env = '{' . env
       let env .= s:closematch(env)
       echo '\begin'.env
-    if env != ""
       let before = '\begin'.env
       let after  = '\end'.matchstr(env,'[^}]*').'}'
     endif