Adding a group as non admin causes error

Currently in master (15.04testing) a user can not create a group - they get this error:

[WAR] eb (lib/form/elements/wysiwyg.php:87) Invalid argument supplied for foreach()
Call stack (most recent first):

    log_message("Invalid argument supplied for foreach()", 8, true, true, "/home/robertl/htdocs/mahara-devel/mahara/htdocs/li...", 87) at /home/robertl/htdocs/mahara-devel/mahara/htdocs/lib/errors.php:441
    error(2, "Invalid argument supplied for foreach()", "/home/robertl/htdocs/mahara-devel/mahara/htdocs/li...", 87, array(size 2)) at /home/robertl/htdocs/mahara-devel/mahara/htdocs/lib/form/elements/wysiwyg.php:87
    pieform_element_wysiwyg_get_headdata(array(size 8)) at /home/robertl/htdocs/mahara-devel/mahara/htdocs/lib/pieforms/pieform.php:1732
    pieform_get_headdata() at /home/robertl/htdocs/mahara-devel/mahara/htdocs/lib/web.php:92
    smarty(array(size 0), array(size 0), array(size 0), array(size 1)) at /home/robertl/htdocs/mahara-devel/mahara/htdocs/lib/errors.php:576
    MaharaException->handle_exception() at /home/robertl/htdocs/mahara-devel/mahara/htdocs/lib/errors.php:467
    exception(object(AccessDeniedException)) at Unknown:0

This is due to a commit 36bc9f7d26076d74ebc6cd0672441eed8ed9cd2d calling group_update on group creation

Will fix up.