evdev-dump-events: show events by name

evdev: add code name getting functions

build: rename dump, use tags for sensors, add convenient targets

follow stdlib net module changes

buttonc: add key combo to signal motion-control

tools: buttonc: use getopt

motion-control: use getopt

motion-control: impl blocking and resetting via signal

add buttons reader for micro:bit

to be used with buttonc

Makefile: fix rules for pointerc, buttonc

tools: add buttonc: send key events from stdin

pointerc: support button events

pointerd: support button events

pointerd: exit cleanly on SIGINT

motion-control: signal: set SA_RESTART

gy-801-dump: signal: set SA_RESTART

motion-control: reduce yaw downscale

this make movements (subjectively?) more friendly in general case

sensors::L3G4200D: enable high-pass filter @0.05hz

this helps with fighting nearly-constant drift

ahrs: complementary: ignore yaw from tilt

math::quaternion: add from_euler