This gets rid of a couple of per-entity sprite bitplane types, makes
sprite declarations easier to read by putting width and height next to
each other… and points out a number of array dimension mistakes -.-
Even in places where we can't use it.
Part of P0138, funded by [Anonymous] and Blue Bolt.
Might look uglier, but has the advantage of not generating an empty
segment with the default name… *and* the default padding, which will
really come in handy with the following breakthrough.
Part of P0137, funded by [Anonymous].
nmlgc