* Use scoped_ptr for condition
* Check solver result in unit tests
* Add test for unusual cjust
* Add solver::get_value
* Broken assertion
* Support forbidden interval for coefficient -1
* Rename to neg_cond
* Add some logging utilities
* Implement case of forbidden interval covering the whole domain
* Implement diseq_narrow
* Do not activate constraint if we are in a conflict state
* comments
* Assert that lemma isn't undefined
* Update revert_decision to work in the case where narrowing causes propagation
* Fix case of non-disjunctive lemma from forbidden intervals
* Conflict should not leak outside user scope
* Add guard to decide(), some notes
* Add test case
* Add constraints to watchlist of unassigned variable during propagation
* Move common propagation functionality into base class
* Combine eq/diseq narrow
* Compute forbidden interval for equality constraints by considering them as p <=u 0 (or p >u 0 for disequalities)
* Separate constraint creation from activation
* Basic recursive handling of disjunctive lemmas for unit tests
* Set learned constraint to true immediately
* Preliminary support for negated constraints
* Add helper to check whether pdd is univariate and linear
* Reorganize propagate/narrow of eq_constraint
* Implement propagate/narrow for ule constraints
* Also push trail instruction in push_viable
* Implement phase saving
* Implement signed comparison on BDD vectors
* Add fdd::non_zero
* Simplify construction of fdds over disjoint variables
* Minor changes to adding constraint
* Coding style
* Simplify bddv class
* mk_eq: run loop from below
* Add unit test for bddv unsigned comparison
* Add test that shows contains_num/find_num fail after reordering
* Add BDD vector subtraction
* Call apply_rec in mk_ite_rec instead of apply
* Question about mk_quant
* Implement quot_rem over BDD vectors
* Move shl/shr to bddv
* Make unit test smaller
* Add class dd::fdd to manage association between BDDs and numbers
* Remove contains_num/find_num from bdd_manager
* Fix XOR over BDDs
* Add operator<< for find_int_t
* Add equality assertion macro that prints expression values on failure
* Adapt contains_int and find_int to take externally-defined bits
* Add more operations on BDD vectors
* Remove old functions
* Additional bddv functions
* Rename some things
* Make bddv a class and add operators
* Fix find_num/contains_num calls
* Add a few helper methods for encoding sets of integers as BDDs
* Use BDD functions in solver
* Add bdd::find_int
* Use bdd::find_int in solver
* Add narrowing for linear equality constraints
* Simplify code for linear propagation
* Add test for later
* Narrowing can only handle linear constraints with a single variable
* Need to push_cjust
