Fix PostBack checking conventions

Conflicts:
	applications/dashboard/controllers/class.importcontroller.php
	applications/dashboard/controllers/class.profilecontroller.php
	applications/dashboard/controllers/class.settingscontroller.php
	applications/vanilla/controllers/class.postcontroller.php
	applications/vanilla/controllers/class.settingscontroller.php
Fix merge failure in tkey fix
Merge pull request #2193 from vanilla/hotfix2-1/tkey

Fix PostBack checking conventions