Design Review Finalization Tweaks

[LFrancis23]

There is a bunch of little things that should be improved for design review. They include but are not limited to the following.

1. LED Functionality: The LED's onboard should be doing more things, some of which I am thinking of are: Mute Indicator, Keyboard connected indicator, Display connected indicator.
2. MIDI Velocity: MIDI velocity should work better, I want to try and get the full 0-127 range if possible.
3. Volume Knob: Increment/Decrement by more than one, probably 10-15 turns for full range so probably around 9-10 values per tick.
4. MIDI Mute: Mute doesn't actually mute, it just kills the active notes, this should be changed. Also add functionality for unmute. Likely requires a "muted" flag in the keyboard struct. Maybe this can be embedded in the volume value? If the max volume is 127, that is |0111|1111| We can use the MSB as a "muted" bit meaning no matter the lower seven, keep volume at zero.
5. Print the current octave and volume.