Feature: Allow mangement of <role>s via admin/ interface.
This allows to manage <role>s via admin interface if the role supports. Also format of admin/manageauth has been changed: - <source> was renamed to <role>. - mount parameter was removed. - <role> got new parameters: type, name, can-adduser, can-deleteuser, can-listuser. - can-* parameters are bools ("true" or "false"). They should be used to show or hide elements on the admin interface. Ticket #2123 is nearly complet with this, just admin/manageauth.xsl needs up be updated. Please close the bug in the commit that updates admin/manageauth.xsl. See #2123