Remove the harcoded logout for hathor as we don't use it

### Tracker

http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=33890&start=0

### Testing
0. apply patch
1. switch BE templat to hathor
2. logout (make sure that it works)

### Why?

The logout code is not used as it is in a comment line / disabled.