-Fixed DMC $4011 write behavior
-Fixed period for square channels
-Removed blip_buffer & blip_synth. Replaced with blip_buf and SoundMixer - now have non-linear sound mixing.
-Fixes all sound-related tests (apu_mixer (dmc, noise, square, triangle) and volume_tests
-Give the number of mismatching frames
-Allow debugger to break when a frame is different
-Fix mismatches between GUI & TestHelper environments (GUI always has four score adapter enabled)