MidiBud version of MidiPal firmware: adds support for five push buttons

Changes are:

* Pressing a button selects one of the first five parameters of the current app
* In User Program pressing a button selects one of the four user programs
* In SH-01 sequencer recording mode pressing button 1 inserts a rest, button 2 inserts a tie, 
  button 3 stops recording and button 5 stops recording and starts playback.
* No Controller app (MidiBud does not have analogue inputs)

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Midipal, the MIDI swiss army knife.

A midi in, a midi out, a small display, an encoder ; 20 awesome features:

* MIDI monitor
* BPM counter
* Keyboard splitter
* Note dispatcher / voice stealing / polyphonic driver
* Channels merger
* Channel filter
* Clock divider
* Clock source, with swing
* CC and NRPN knob
* 8 pots/sensors voltage reader/controller
* Drum pattern generator (including Euclidian patterns)
* Note, velocity and CC randomizer
* Chord memory
* Arpeggiator
* Sequencer
* CC lfo
* Tempo-synchronized note delay (with transposition and decay velocity)
* Slave start/stop synchronizer (à la Mungo Sync)
* Scale processor / harmonizer
* Ear training game