Move cv mod calculation to processClockTick. This is less ideas because it is an ISR, but it saves a significant amount of memory. Performance doesn't seem to take much of a hit.
Reviewed-on: https://git.pinkduck.xyz/awonak/libGravity/pulls/24
This now matches original Gravity behavior. Also, now when applying CV mod positive voltages increase clock mod instead of reducing it.
Also fix pulse out, which wasn't previously updated when CLOCK_MOD was moved to program mem.
Reviewed-on: https://git.pinkduck.xyz/awonak/libGravity/pulls/16
