Add Unit Types onto models

[nstephenh]

Add unit types and subtypes onto models. I've started this in #3160.

Consider removing them from units, unless we really need them on units for something like "cannot select units with the infantry keyword"

Add missing unit types in

Clean up "Vehicle" and "Vehicle Unit"

[nstephenh]

Most of the unit types are now handled, but there are still a few for consideration:
Fortification
Building
Deathwing, dreadwing, firewing
Psy-automata

And then a large number of misspellings of infantry, one misspelling of transport, and one transport with an asterisk.