Project Melody v0.2.6

This release has some new features to it (there is the occasional bug where the midi generation will fail)

What's changed?
number of notes in melody will only affect the melody now. Chords and Arpeggios will be based off the chord progression.

Chords and arpeggios are now fully based on chord progressions predefined instead of randomly selecting notes from a scale.

Musical Elements now has a selection for all which will create a midi file that will have a melody, arpeggio and chord progression all in one and make sense in a musical context.

There are now a lot more rhythm patterns that will be chosen from when creating melodies, arpeggios and chord progressions.

There are around 20 chord progression types implemented from common chord progressions used in songs.

Chord Generator class has been updated a bit. It will now get discern chord types from scale degrees (this has not been added to the main library repo as of yet).