Corrected hash computation so that Perm32 and PermArray match.
Shiftable permutation support.
Additional tests for hashCode / base change.
WIP working base change.
Bugfixes and speed ups in chain construction/base swap.

Corrected two bugs in chain construction and node conjugation.
Added mutable chain conjugation.
Made base swap preparation faster by removing redundant updates.
Added chain conjugation test.