music-notation

Describe the bug
Stave lines in palettes are quite noisy in places. We could fix this by applying a 50% transparency, or simply choosing a softer colour for them. (I can supply the colours if needed)

Example:
Original:

Becomes:
<img width="111" alt

As discussed here it is currently not possible outside of alphaTab. alphaTab keeps properly track of the active beats for highlighting purposes but an integrator cannot obtain this list for any custom purposes.

But the playedBeatChanged is only called with the beat which is used for cursor placement.

The idea would be to add a `act

Description
Allow custom fret labels (attached to instrument, player, or tuning) to allow other instruments that don't just use numbered frets/positions.

For example, shamisen players have the following:
0 -> 0
1 -> 1
2 -> 2
3 -> 3
4 -> #
5 -> 4
6 -> 5
7 -> 6
8 -> 7
9 -> 8
10 -> 9
11 -> 1b
12 -> 10
13 -> 11
14 -> 12
15 -> 13
16 -> 1#
17 -> 14
18 -> 15
19 -> 16
20 -> 1

Now that we are disabling .trimValueWhitespaces from our decoder, it may make sense to create an XMLDecoder subclass MusicXMLDecoder.

This way we can use MusicXMLDecoder when testing atomic units, so we know we are working with the same thing when decoding a whole MusicXML object.

This will also allow us to wipe XMLCoder from testing, which has seemed slightly out of place.