Change hash functions for uint32_t integers and 64 bit integers.
Change hash functions for uint32_t integers and 64 bit integers.

The previous function based on Knuth's multiplicative method work pretty
well if the keys have small values but the results are bad if keys vary
in the upper bits.

The new hash functions are based on Thomas Wang's hash functions. (http:
//web.archive.org/web/20071223173210/http://www.concentric.net/~Ttwang/t
ech/inthash.htm)

mloy/cjet,gatzka/cjet,mloy/cjet,mloy/cjet,mloy/cjet,gatzka/cjet,gatzka/cjet,gatzka/cjet,mloy/cjet,gatzka/cjet