math/cadical 3.0.1 OpenBSD

The goal of the development of CaDiCaL was to obtain a CDCL solver, which is easy to understand and change, while at the same time not being much slower than other state-of-the-art CDCL solvers.

Originally we wanted to also radically simplify the design and internal data structures, but that goal was only achieved partially, at least for instance compared to Lingeling.

However, the code is much better documented and CaDiCaL actually became in general faster than Lingeling even though it is missing some preprocessors (mostly parity and cardinality constraint reasoning), which would be crucial to solve certain instances.