First draft of a new Infer.  It typechecks, but it still has a bug.  Actually, it might be the same bug as BEFORE this overhaul, so maybe it was preserved.
Debugging with Sam.  Added chatter, found the problem.
Update submod and bump lvish dependency
Fixed the bug we identified with IM.copy.  But there must be something else, because Infer.hs isnt passing any tests atm.
Fix major bug where "winner" neglected to call the continuation.
This makes some of the tests (10/18) pass.
WIP: refactor all references to the varmap representation in preparation to
make it switchable to SatMap.
Change the common interface to VarMap.
Bump LVish dep.  Further refactor common VarMap interface.
Finish switch over to SatMap.  This FIXES treecall... it must be a problem with the PureMap version.