INCOMPLETE
BROKEN

Getting some sort of bug with updates where the first update (initial
state) is missed by some consumers. This may be a race condition with
multiple consumers. Seems strange though. Happened all of a sudden after
apparently unrelated changes.

My theory is that this is causing state to be missed, because prev is
probably null.

Yeah, membranes are actually _not getting_ the first update because it's
somehow getting missed. Not sure if this is all membranes.
Clean out old stuff
INCOMPLETE write in tandem with accumulation
INCOMPLETE slowly adding back state switching
Remove membrane(), unit -> widget
Add back RB expanded write
Toggle cancel
Include overlay in transition
Fix bug with widget and first state
Solve nullish prev state at membrane level
TOTES BROKEN
PARTIAL
UNTESTED split out patches and state.

Use reductions and dropRepeats now that we have a simple patch function.
Fix problems with downstream state test and dupes
Kick off accumulation simultaniously w/ view

This makes sure we don't miss any events
Comment
Remove "judge" comparison functions

Make write() accumulate with target
Add settings overlay
hub() return value of drags()

Prevents broken chains when multiple accumulation happens on result.

* Update accumulators.js
* Check defaultPrevented in haltEvent_()