Added 4 more abstractions

detect_edge takes a signal and outputs bangs upon rapid transitions

lfomaker_ply is an abstraction for the poly object for creating swarms
of phasor~ lfos. takes target messages and a central timing phasor~

square takes a phasor~ and turns it into a square wave for timing
purposes. Swing can then be controled by puls modulation

timescale takes a timing phasor~, scales it, and outputs a signal rate
metronome with swing (bang)