added doc
first somewhat testable version using arrays for all objects
existing issues marked with "todo"
moved presets and sequence setting over to MPAudioManager public interface and using that in ViewController now
- sequence length is now correctly determined based on longest track + added property
- renamed forChannel into forChannelIndex to avoid any confusion (indices are always 0-based)
- music player is now setup to handle up to 16 channels
- if soundPresetName is empty string, no preset will be loaded for the corresponding channel
- currently channel strip contains: sampler --> limiter --> mixer
- some more logging
- sequence name and sound preset names can now be set from outside MPAudioManager
delay and reverb units are in again as well (and working)
- reduced number of channels to 10 because running on physical device is very heavy on CPU (nearing 80%)
- pitch shifters can be added, but they are much too heavy on CPU, as expected: we'll need to decide what to do with this
- tried compressor again: as soon as it's added the graph initialisation fails (probably due to the audio format that is changing!)