Feature/kpaxman add missing layout builder perms

Could you review and merge if this is enough to take care of the missing permissions as identified in https://jira.uwaterloo.ca/browse/ISTWCMS-4681?focusedCommentId=143255&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-143255 ? (Should any tests be updated as well?)