better modularization: moved SMT configuration options and diagnostics as well as SMT failure and exception into separate structures (both of which are loaded first and consequently are available to other SMT structures)

merged

corrected slip: must keep constant map, not type map; tuned code

constructors to datatypes in code_reflect can be globbed; dropped unused code

adding code and theory for smallvalue generators, but do not setup the interpretation yet

make sure the SMT solver runs several iterations by lowering the timeout at each iteration -- yields better results in practice

better detection of completely irrelevant facts

always use a hard timeout in Mirabelle

use "smt" (rather than "metis") to reconstruct SMT proofs

don't pass too many facts on the first iteration of the SMT solver