anduril: test suite

[Selene ToyKeeper]

This is probably not necessary, but it'd be nice for Anduril to have a test suite of some sort to verify quality before production releases.

For the most part, it's pretty straightforward... go through the UI chart and test each function, then do some monkeys-at-typewriters tests to make sure it doesn't explode when given totally random inputs. There may be specific non-obvious things to test for though, and it'd be nice to document these somewhere.

For example, until recently, there were some issues when the user would click N+1 times and hold the final click, where N was the value of MAX_CLICKS. And there are little UI details not actually documented anywhere else, like making sure the hold-from-off action has the same timing in both stepped and smooth ramp modes. And some things are hardware-specific.

I don't really want to duplicate the user manual though, since that would be redundant. So maybe it should only include the non-obvious cases.