use lower order bits in prng

- This is about 2 times faster compared to the previous rng.
- Add unit tests to ensure things are correct
- Update integration test data
re-enable integration tests (thanks to van51!)
Update tapkee with manifold sculpting merge and 'external' randomization routines
Basic random_shuffle as an attempt to fix a crasher
Refactored converter_tdistributedstochasticneighborembedding_modular.py test and un-blacklisted it; re-generated data for this test.