One, TMW->EWTS gives dbas and dngas instead of dabs and dangs
because Chris Fynn's e-mail from today has dbas and dngas.
Second, Down with ACIPRules. Long live ACIPTraits. EWTS->Tibetan
conversion is closer still.
conversion. The tag 'TODO(DLC)[EWTS->Tibetan]' exists all over the
place. EWTS->Tibetan isn't here yet; lexing isn't here yet; this is
mainly a refactoring so that the ACIP->Tibetan code can be reused to
do EWTS->Tibetan.
I'm committing this because tests pass (it shouldn't be breaking
anything), because I want a checkpoint, and because the laptop this
sandbox was on isn't my preferred development environment.
