WIP - Split Mongo Documentation

Split itself doesn't care how many or what branches exist. In fact, I designed it explicitly to support arbitrary branches so that we can support other workflows using branches such as this complicated sequence of branches--future, draft, review, test, beta, and live--where future are just ideas which may go in the next release, draft is the honing of those ideas, review is what's ready for the bosses of the course team to review, they then push to test for whatever test group to try out and then push to beta and finally live. Of course, to be useful, all the editing must occur on the firstmost branch so that changes don't get lost, but because publishing taking parts of branches and promoting them to the "next" branch, that works.