intermediate checkin: working on timer

was about to start handling the scheduling for cycle counted events the
same way as for real time scheduled events, but i think i'll switch over
to using `<util/atomic.h>`, if i can
finished messing with timer :) (for now)

main.c is now out of the timer business (except for "ticking" cycles...
since there really is no other way to guarantee something runs exactly
once per scan cycle)
comments, and a small function name fix