Fix visualizer sleeping too long

The documentation for ugfx gEventWait wait is wrong and the
function takes the time in milliseconds, instead of system ticks.
This caused the the thread to sleep way too long. It also caused
somewhat random sleeping behaviour as the MS2ST function overflows
at around 43 seconds sleep.

The event source is also now initialized correctly, so that the
thread actually can be woken up by events.

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