Add ability to set staff lock from course outline

STUD-1851. @cahrens please review.

Sandbox available at http://studio.benmcmorran.m.sandbox.edx.org/course/edX/Open_DemoX/edx_demo_course
Typo, missing "and". 

Recommend "If publish is set to 'republish' and this item is not in direct only categories and has previously been published, then this item should be republished."