Half-assed Emacs mode for Foswiki/Twiki

Here's my attempt at getting a working Foswiki/TWiki mode for Emacs based on Org-mode. I've started taking this good work and mangling it; my excuse is that I'm only just starting to program Emacs.

What works so far: cycling visibility with tabs and detecting levels. Hey, it's a start. :-) Next up is getting Meta-left/-right to work to promote/demote headings; I'm not sure if I should be doing this with Emacs advice, or if there's some other way to locally override a function's definition. Answers on a postcard to aardvark [ta] saintaardvarkthecarpeted [tod] com 'til I get comments sorted out.