[Fix] Email Regex corrupted when #685 was merged

Weird that nobody saw that for so long... See the original .diff here:
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_id=8103&tracker_item_id=29997
http://joomlacode.org/gf/download/trackeritem/29997/78299/%32%39%39%39%37%2e%64%69%66%66

Test validating various emails.