Improve PWM jitter.
This modification is a bit troubling as it makes interrupt routine busyloop for about 16us, this however is just about 1-2% (depending on channel values) of CPU time so I see this can be tolerated. With this change the servo jitter is virtually nonexistent.
Change scanner mode to start with 'module' min/max frequencies.
- move PPM output setting to bind_data (no more need for jumpper)
- revise PWM output code to cope with upcoming HW
- update scanner interface for more sane units