Add support for new OpenNBS format

[underscoren]

Not sure if you still care about this neat little library, but wave-amp shows up as the first google search for "computercraft music player" so i think some people would still be interested

I added support for the new 1.12 and 1.14 instruments (guitar, xylophone, bit, pling, etc), as well as support for the new OpenNBS format since the old NBS project has been discontinued.
Only OpenNBS format v4 and v5 are supported, and if the user tries to wave.loadTrack() a file that's using an older format, the library will throw an error (Original NBS files still load fine though). Not sure if that's the kind of behaviour you want, but it should be easy enough to change to something like return nil.

Using this, I was able to get wave-amp to work in CC: Tweaked (again, because ComputerCraft has been discontinued...) on minecraft 1.16.3 without any changes, and play some songs in the new format. I haven't tested it on older versions, so I'm not sure if there are any regressions from these changes.

[CrazedProgrammer]

Hi underscoren, thanks for writing this PR. Apologies for the late reply - I have been on a bit of a hiatus since graduating from college.

There are two things that put me off from merging this PR:

• OpenNBS versions 1-3 are not supported.
• It hasn't been tested on any version of the original ComputerCraft mod.

If you're still interested in tackling these two points, I would definitely consider merging it.
If not, I'll keep this PR open so other users can easily find it.

[underscoren]

Wow, I forgot I even made this PR what a blast from the past!

I'm a bit limited with free time at the moment, and I haven't properly played modded minecraft for a few years, but I'll see what I can do. There's probably a new NBS format, and I'm certain there's been advancements in ComputerCraft-esque mods, and minecraft itself.