If available (sometimes, say a top level expression, it might need
inferring so there'll be no goal available). Also add the ability to log
the current goal, or indeed any term.
Still all they can do is check and log. Now scripts must return
something of type TT, which is in practice a TTImp that goes to the
elaborator for final checking
Add %runElab and start on scripts, although all they can do so far is
check a term. This does gives us, sort of, "template Idris" (as
demonstrated in test reflection002)
Don't get too excited yet - I want this in so that it doesn't get too
out of sync, but I still have to think about exactly how it's going to
work in practice.
