RESTful refactoring for course_info
both updates and handouts.
Handouts uses a supposedly general xblock aka module_info model.
Code review changes
Separate the course info update rest interface from the course_info page.
More fixups from code review
Use the course_info update locator for the url in the client not the course.
GET can get all or a specific one
separate getting the html page w/ both updates and handouts from interacting w/ updates.