Added 1 ms offset to attack an release, to avoid clipping with 0 value. It seems that it's already implemented in the Audio Library, so it needs mors investigation.
Added filter mode function, to switch for band pass to a band stop filter with knob mid-course.
Modified readme to specify libraries used.
Function settings added : keymode (keytrack), retrigger (legato), detune, bitcrush, midi in & out channel setting.
All function settings are saved to eeprom.
Added optional detune for analog-like sound, with three level of setting.