It's the same as &hank-emisar-d3aa, but needed some minor tweaks:

- wait longer before measuring the battery,
  because it's hard to tighten the tailcap fast enough

- ramp adjustments to compensate for slightly different "gear ratio"

(side effect: also enables RGB front aux while main LEDs are on,
 since the two are a single circuit internally and can't be separated)
(changed at Hank's request)

After testing on every device I can, and getting several users to also
test this, it appears to reduce and sometimes completely eliminate
preflash on most devices... and the cases where it wasn't reported to
help, at least it didn't make things worse.  Some units apparently just
can't get the flash eliminated completely, despite trying lots of things.

Instead of turning the chips on and then waiting 4ms, it now turns the
preflash absorber on, waits ~0.6ms, sets misc params, then turns the
boost chip on, then waits ~0.6ms, then turns the preflash absorber off.

This seems to work best on li-ion power, where on my devices it completely
eliminates any preflash.  There is still a very mild flash on AA though,
which I wasn't able to get rid of.  But it's like... 0.003 lm for just
a few milliseconds, really not bad.  Even in the worst case reported by
a user, based on the video they took, it looks like just 0.01 lm for
a few milliseconds.

for some reason, and didn't commit... saving now to change branches,
but should delete this commit if it turns out there was no reason for it

- calibrated party strobe
- removed duplicate or commented-out code
- added a basic readme

- changed model number from 0281 to 0171
- cleaned up blink_negative and AUXLED_RGB_DIFFERENT_PORTS a little
  (but the latter needs a complete refactor, as soon as the
   hardware abstraction code can handle aux LEDs better)
- cleaned up USE_LONG_BLINK_FOR_NEGATIVE_SIGN a little
- removed USE_OTG_IN_MOMENTARY since it's not actually used
- moved hw/loneoceans/lume-x1-avr32dd20/* files into hw/hank/lume-x1/
- superficial cleanup on hank/lume-x1/hwdef.*
- removed some of the extra stuff from hank/lume-x1/anduril.h
- adjusted calibration (especially ramp table) on hank-lume-x1
  (ramp shape is pretty close to a D4K-boost now, but with more firefly modes)
  (calibration is based on a sample size of 1, further testing needed)

The [PR](https://github.com/ToyKeeper/anduril/pull/37) has a lot of other
stuff in it, so I'm just picking out the parts needed for this particular
light, and leaving the rest for later.

Will need further edits before merging into trunk.