REF: move Interpolation and related crossfading code out of TextureEffect, into a new Interpolator class. ENH: allow external Animators to subscribe to a Mixer's animation loop. ENH: start sketching out the dairy scene's shuffle mode.
ENH: crude step sequencer for shuffling the looks and switching between Woven and not-Woven on a schedule.
ENH: randomly select easing curves when fading in and out tracks
ENH: shuffle mode complete, except for its kill switch. Woven finale timing tuned.