The control character procedures can be control->graphic and
graphic->control, which is standard terminology.
LGTM.
Instead of `ascii-space-or-tab?` it could be `ascii-space/tab?`.
Eh. Not worth it.
I read the new commits. Are you referring to the problem with which
version of Unicode to follow?
It's not so much that, it's that Java 1.0 made up its own rules for determining (e.g.) what else is a letter besides the characters in general category L*. Unicode has now caught up with those rules and superseded them, even in the Java library.