Implement retunable primes

[euwbah]

Implements #62 using the following syntax:

(primes: <a> <b> <c> ...)

Where a b c ... are interval tunings of consecutive primes 2/1, 3/1, 5/1, 7/1, 11/1, etc...

The example below will play

• 2*2 / 2*2: rootHz
• 5 / 2*2: 51 steps of 22 edo above rootHz, minus (2/1) x (2/1) = 7 steps of 22 edo (down major third)
• 3*2 / 2*2: 1900c above rootHz plus (2/1) minus (2/1)x(2/1) = 700c (7 steps of 12 edo perfect fifth)
• 7 / 2*2: 87 steps of 31 edo above rootHz, minus 4/1 = 25 steps of 31 edo (augmented 6th)

(primes: 2/1 1900c 51\22 87\31) 4:5:6:7

the primes: token is implemented as a Setter under the type SetPrimes, so it can be chained together with other setters in a SetterGroup, e.g. (primes: 12\12 19\12 28\12 34\12; osc:square8) 4:5:6:7

More examples and details are written in the 'info' tab. A simple parsing test was added to grammar.test.ts under 'should parse sequence with primes tuning setter'.

Additional fixes:

• Fix invalid ratios causing browser freeze
• Improve generalized pitchDegreeWrap and ratioWrap calculations

[euwbah]

Tested & ready for review @dxinteractive

[dxinteractive]

Hey @euwbah - I'm so sorry I missed this for so long! Thank you for putting all this effort in, including basic housekeeping that I haven't got around to. I'll review and leave some comments, but for the most part it looks great!

[dxinteractive]

Thank you for including these! Apologies for not having build instructions - I didn't originally intend for this to be an open source project so I'm been slack on that front. My hidden intent is that yarn prep should execute everything required to prepare the project - if you could wrap these build steps up inside of yarn prep that would be fantastic.

[dxinteractive]

I might suggest cd packages/xenpaper-app && yarn start, as it'll spin up a local dev environment with hot relaoding courtesy of create react app. Even better a "start": "yarn lerna run start", would be even better - the developer-facing command would then become yarn start.

[dxinteractive]

Would it be possible to add retunable primes to the grammar using {primes: } rather than setters ()? The reason being that syntaxes using { are intended for scale modification, and ( is intended for all the non-scale settings. Everything else about this syntax looks great.