Mini-notation for fraction shorthands

[yaxu]

The tidal mininotation has these shorthands for fractions:

'w' 1
'h' 0.5
'q' 0.25
'e' 0.125
's' 0.0625
't' (1/3)
'f' 0.2
'x' (1/6)

It allows a prefix factor, e.g. 5s is parsed as 5/16ths, 2t as 2/3rds etc.

e on its own would be 1/8th, unlike for notes where it would be parsed as the note label for 4.. I.e. notes are parsed differently from other numbers.

Explicit ratios can be given with %, e.g. 3%7 would parse to 3/7. (/ can't be used as that's taken by 'slowing down' steps).

Part of #30.

[felixroos]

this is potentially blocked by #483

[felixroos]

one way to implement this: #793

@yaxu how to find out which params of which functions in tidal get parsed as fraction shorthands?

[yaxu]

@felixroos note and n (and up, which is now an alias of note) are the only ones parsed as notes, so fraction shorthands work for everything else.

[yaxu]

Now I've worked out how to type ⅓ and ⅜ on my keyboard (super/windows key followed by the numerator and denominator), I'm thinking it could be nice to support those in the mininotation.

These are the available fractions in ascii: ½ ⅓ ⅔ ¼ ¾ ⅕ ⅖ ⅗ ⅘ ⅙ ⅛ ⅜ ⅝ ⅞

There's more in unicode, but without editor features, they're harder to type.. You can also construct them like ¹³¹⁄₁₂₄

[yaxu]

I guess the problem with #793 is that without type inference, things like .off("t s".div("2"), ...) are tricky