grid module: incomplete support for fingers{} and count{}

[andr-ew]

unsupported:
momentary.fingers (kind of works but buggy)
toggle.fingers
toggle.count when toggle.edge == 0
trigger.count
trigger.fingers[2] acts more like trigger.count[2]

value is the correct implementation of fingers, momentary & toggle is the correct implementation of count

TODO: refactor binary and most of the other handlers to mimic these correct behaviors. this will probably take the form of helper functions or sub-objects rather than supertypes, this way the new behaviors can be shared by controls in other modules (_key). maybe some specialized helper tools would make sense within the core module.

[andr-ew]

added support for trigger.fingers and toggle.fingers but only in the 1d routines, logic needs to be mirrored in the 2d routines

andr-ew/nest@9f51c6d
andr-ew/nest@439caca