add editor for envelope parameters to the UI

add subbeats (play a note between the main beats, like 8ths in a 4/4 Rhythm)

fix problem where an instrument would not stop playing when deleted

add grid to edit a Voice's pattern

add dialog to edit voice (non-functional)

ensure dragging instruments only works vertically

add drag and drop for instruments in their list

add a button to remove an instrument from the list

add functionality to the add instrument button

add voice selection

rewrite Voice

fix issue where keeping the default chord type would not update correctly

add solo button for an instrument

fix issue where the waveform for an instrument would be reset when reopening its properties window

beautify mute toggle

add individual volume sliders to each instrument

move waveform selection to the instrument editor windows

add instrument editor

add GPL v3 copyright

fix issues with chord views in play section

add song navigation buttons

fix issue where the chord preview in the play section would not update when the first phrase is entered

add preview for the first chord of the upcoming phrase

refactor PlayFragment.kt

add tempo modifier

refactor Song to use Cycles

add current phrase preview to Play section (with issues)

add beatCallback to Song

fix crash when no chords have been added

remove the action bar