fixing bug580 caused by bad bv inequality explanation
Refactoring of conjecture generator.  Determine subgoals are non-canonical based on ground equalities.  Add filtering options to options file.
Bug fix variable triggers with --inst-max-level : use term in EQC with minimal instantiation level.
More refactoring of conjecture generation.  Term generation into own class.
Refactor entailment filtering for conjecture generator.  Other minor cleanup.
Fix soundness bug for quantifier macros involving Int/Real.
Fix (push) and (pop). Thanks to Christoph Sticksel for the bug report.
Merge branch '1.4.x'
Fix fix. There are no unsat cores in 1.4
Merge branch '1.4.x' while ignoring commit 8d5eb49.