1. Use new dialog menu hacks (no strings, just arrays of dialogMenuItem structs)
so that I can create composite menus with radio/checkbox/... items in them,
removing some long-standing UI bogons in various menus. This work isn't
finished yet, but will be done in two phases. This is phase one.
2. Remove all the script installation stuff. I never got time to document it,
it was arcane and it just complicated much of the code. There are better
ways of doing this if I want to do auto-driven installations later.
3. Remove much dead code and otherwise attempt to remove as much historical
grot as possible so that this code is easier to hack on. This is also
a two-stage process, phase one of which is now complete.
don't bogusly restore the screen to the message that was the cause of the
abort. That resulted in lots of weird flickering dialog boxes that appeared
to be displayed out of sequence.