* add pre commit hook
* hash mixer and combiner in C
* tests for hashes
* bench of hash
* fix warnings
format and minor fixes
* format
* doc
* test hash: add a per-bit distribution check
* hash tests: count bit probability
* cchash64: add apply and combine*
* makefile
* cleanup hash bench
* change cchash constant
from murmur2
* make the hash test stronger
