Add Drop code

[devramsean0]

Gradually speeds up a drum (any players) in a specified number of bars (the buildup), (from dur = Clock.bar_length() to a target dur) then solos it for another specified number of bars, then optionally ends the player while it unsolos.

Example:

b1.drop(buildup=2, target =1, solo=2, end=False)

Put on instrument, will start the duration at the bar length and half it every time until it reaches a certain value. Doesn't start until next bar.

[mr-eggleton]

FoxDot's default play() duration is 0.5, and the way it plays sound better with the option to use Euclidian patterns and a default buildup of 4 bars so this should be

b1.drop(buildup=4, target=0.5, euclid=False, solo=2, end=False)