WIP pwm
I've been working on some good documentation for PWM. It's definitely not finished, but I think this is already really neat. It's an interactive way of explaining PWM (Bret Victor style), which may be easier to understand.

Updated a bit with some code samples (and an incomplete interactive counter/channel example). Definitely not finished, as the code hasn't even been written to implement this PWM but I wanted to make sure that explaining how this works is not too difficult.
I love this page, can we probably re-vive it and add to the site? I'll try to cross-check the examples with the current codebase, rebase on dev's head and probably add a servo example.