Fixed a bug, that prevented some characters displayed in a raid.

If multiple character without user assigned was signed for a raid, only
one of them were displayed.
Joomla 2.5.4 changed how timezones are stored, now used as string.

RaidPlannerHelper::getTimezone now by default returns timezone as
offset in hour.
Changed Radio buttons in signup form to make Bootstrap compatible.
Fixed signup window, now user can edit their previous settings.
Merge branch 'master' into development

Conflicts:
	administrator/com_raidplanner/helper.php
	manifest.xml