Add a nicer sine based gradient for the LEDs

Make LED visualization times configurable

Fix emulator #ifdef check

Don't include lcd_backlight_hal for emulator

Add callback function for emulator drawing

Add custom led and lcd display support

Fix crash when event listener not created

Build lcd_backlight_hal_emulator.c

When the emulator is set, instead of the lcd_backlight_hal.c file.

Enable and fix compilation of more files

Use ugfx API instead of chibios

Makefile changes to support emulator build

Merge branch 'master' into led

Merge branch 'chibios-contrib'

Update include dir for new serial_link include

Configurable visualizer thread priority

Fix compute_gradient_color

Fix a few led test animation issues

Fix some makefile issues, and symbol issues

Run mirrored keyframes for led tests as well

LEDS are flushed automatically

After running the animation, instead of having to do it manually.
This avoids duplicate flushing, and better support for cross-fades.