Mailing sometimes failed because of non-escaped slashes 

When trying to mail if one of the arguments contains a slash an empty mail would be send. This happens mostly if a postprocessing script is set.

The fix is to show the filename only (not the full path). I couldn't get the slashes to escape properly. As the escaped string would have to be escaped as well before it's used and after a while I lost track of the amount of regular slashes and escaped slashes to use. I'd see this as a temporary solution.

We have to find a nice way to escape, as the bug will still occur if the template of the mail contains slashes. If someone has suggestions for this, don't hesitate to contact me so we can find a solution that's more permanent.