Fasttracker II clone v1.64

• Increased number of precision bits for song BPM, playback time counter and audio->video syncing. This is a minor change and does very little in practice as the previous precision was already quite good.
• Audio/video sync timestamps are reset every half an hour to prevent possible sync drifting after several hours of playing a song without a single song stop (resets timestamp) in-between
• The HPC timers are reset every half an hour instead of every hour. Video (if no vsync) and the scopes use these timers.
• Small code refactor for how the song is timed/ticked. Longer song-to-WAV renders may have a filesize change of a few bytes, but this is actually more correct.