Three things:

Three things:
1. Infrastructure for unit T-conflicts added to SAT proxy
   (and also the theory output channel documentation);
   previously theories could not communicate unit T-conflicts
   with the SAT layer because that layer had an implicit
   assumption (not asserted) that the conflict nodes were an AND.
2. UF now pre-rewrites trivial equalities to "true".  These could
   conceivably occur in artificial benchmarks in this form:
     (let (?x BIG-HUGE-TERM) ... (= ?x ?x) ... )
3. The SMT-LIBv2 printer now properly prints Bool constants.