Made apu frame updates depend on master cpu clock

- Made apu frame updates dependent on master cpu clock.  Chose to update
sample every 40th clock (approx 44100 samples/second... ~1790000/44100 =
40.58)

** 091111a - SAMPLING RATES WAYYYY OFF. Added master CPU cycle, haven't
done anything with it (working)
- Added some code for master CPU cycle, but have not done anything with
it
- This is a save before testing out code with master CPU cycle
- Sampling rate of writeBuffer is 1/2 of CPU frequency (~880000
samples/sec), when it should be around 44100.  This is causing the write
buffer to constantly fill up over and over before the read/play buffer
gets the next set of contiguous samples.