Don't twice escape the directory

Mkdir already is already called with an shellescaped parameter. No need
to quote it a second time for the Rmdir() call on VimExit.

Closes issue #22, reported by Daniel Hahler, thanks!

autoload/SudoEdit.vim

@@ -89,14 +89,15 @@ endfu
 
 fu! <sid>Mkdir(dir) "{{{2
     " First remove the directory, it might still be there from last call
+    " parameter 'dir' is already shellescaped()!
     call SudoEdit#Rmdir(a:dir)
     call system("mkdir ". a:dir)
     " Clean up on Exit
     if !exists('#SudoEditExit#VimLeave')
         augroup SudoEditExit
             au!
             " Clean up when quitting Vim
-            exe "au VimLeave * :call SudoEdit#Rmdir('".a:dir. "')"
+            exe "au VimLeave * :call SudoEdit#Rmdir(".a:dir. ")"
         augroup END
     endif
 endfu