Bug 1705 fixed : User cannot add comment with double quotes

Merge from trunk

git-svn-id: http://piwigo.org/svn/branches/2.1@6424 68402e56-0260-453c-a942-63ccdbb3a9ee

include/functions_comment.inc.php

@@ -158,7 +158,7 @@ INSERT INTO '.COMMENTS_TABLE.'
   VALUES (
     "'.$comm['author'].'",
     '.$comm['author_id'].',
-    "'.$comm['content'].'",
+    "'.pwg_db_real_escape_string($comm['content']).'",
     NOW(),
     "'.($comment_action=='validate' ? 'true':'false').'",
     '.($comment_action=='validate' ? 'NOW()':'NULL').',