Ext Clock advances strangely with odd timings

[cosmikwolf]

Steps to reproduce:

1. set up Ext clock with a gate input
2. set step count to 5
3. set clock div to 1/7

clock advances real weird like!

[cosmikwolf]

So I moved from the masterclock interval counter to using the CPU cycle counter to drive the sequence engine post pulse counts. It seems to have helped the issue a bit, but I think the issue lies in the masterclock function. The master clock function needs to be moved to also use the CPU cycle counter, because the tiny discrepancies that pop up are accentuated by the odd timings. Using the CPU cycle counter should be far more accurate, and I think will allow strange timings to work much better.

[cosmikwolf]

Fixed this in 17G.

there was a bug when generating the current frame. I was doing a modulo of frames per sequence before adding in the frames since last ppq pulse. It was causing a cascade of failures and timing issues. Also moving to cycle count instead of master clock count helped significantly.