Merge pull request stephpy#2 from nishigori/check_php_cs_fixer_exists

Added check g:php_cs_fixer_path file exists

Author: stephpy

plugin/php-cs-fixer.vim

@@ -18,6 +18,9 @@ if exists('g:php_cs_fixer_config')
 endif
 "}}}
 
+if !filereadable(g:php_cs_fixer_path)
+  echoerr(g:php_cs_fixer_path.' is not found')
+endif
 
 fun! PhpCsFixerFix(path, dry_run)
     let command = g:php_cs_fixer_command.' '.a:path