Add MIDI as music file format

[infratec]

Since libmodplug does play MIDI, please add this feature.

The link modplug in the help of Music points to this page:
https://modplug-xmms.sourceforge.net/

The new page is this:
https://github.com/Konstanty/libmodplug

- Plays 22 different mod formats, including:
MOD, S3M, XM, IT, 669, AMF (both of them), AMS, DBM, DMF, DSM, FAR,
MDL, MED, MTM, OKT, PTM, STM, ULT, UMX, MT2, PSM
- plays timidity's GUS patch files (*.pat):
a multi sample pat file with n samples can be played with a Frere Jacques
canon with n voices.
- plays all types of MIDI files (*.mid)

Or use native API, all OSs can play MIDI.

[infratec]

Btw. there is not listed in the help what kind of files the Music library plays.
It stays a bit in the dark.

[miso]

+1 libmodplug

[Quin]

Wow, seemingly libmodplug has stepped up their game in recent years.
+1