Merge remote branch 'upstream/develop' into develop-next

Conflicts:
	include/class.client.php
	include/class.usersession.php
Merge remote branch 'upstream/develop-next' into develop-next

Conflicts:
	include/class.client.php
	include/class.usersession.php
Merge remote branch 'upstream/develop-next' into develop-next
Destroy staff session on logout