Adding improved 64-bit hash functions.
Adding improved 64-bit hash functions.

I tested this by computing 1024^3 hashes of 4 randomly-generated input
keys. No collisions were detected.

salazardetroya/libmesh,balborian/libmesh,coreymbryant/libmesh,permcody/libmesh,pbauman/libmesh,friedmud/libmesh,cahaynes/libmesh,hrittich/libmesh,hrittich/libmesh,svallaghe/libmesh,balborian/libmesh,dmcdougall/libmesh,dschwen/libmesh,capitalaslash/libmesh,dmcdougall/libmesh,90jrong/libmesh,karpeev/libmesh,BalticPinguin/libmesh,salazardetroya/libmesh,capitalaslash/libmesh,jiangwen84/libmesh,Mbewu/libmesh,aeslaughter/libmesh,hrittich/libmesh,aeslaughter/libmesh,BalticPinguin/libmesh,libMesh/libmesh,giorgiobornia/libmesh,jiangwen84/libmesh,hrittich/libmesh,Mbewu/libmesh,karpeev/libmesh,capitalaslash/libmesh,coreymbryant/libmesh,giorgiobornia/libmesh,pbauman/libmesh,libMesh/libmesh,vikramvgarg/libmesh,karpeev/libmesh,karpeev/libmesh,BalticPinguin/libmesh,roystgnr/libmesh,pbauman/libmesh,dmcdougall/libmesh,coreymbryant/libmesh,dschwen/libmesh,balborian/libmesh,vikramvgarg/libmesh,balborian/libmesh,90jrong/libmesh,cahaynes/libmesh,90jrong/libmesh,Mbewu/libmesh,90jrong/libmesh,Mbewu/libmesh,dmcdougall/libmesh,pbauman/libmesh,hrittich/libmesh,dmcdougall/libmesh,capitalaslash/libmesh,roystgnr/libmesh,giorgiobornia/libmesh,cahaynes/libmesh,permcody/libmesh,dknez/libmesh,roystgnr/libmesh,benkirk/libmesh,pbauman/libmesh,aeslaughter/libmesh,roystgnr/libmesh,cahaynes/libmesh,benkirk/libmesh,90jrong/libmesh,vikramvgarg/libmesh,aeslaughter/libmesh,vikramvgarg/libmesh,benkirk/libmesh,jwpeterson/libmesh,hrittich/libmesh,balborian/libmesh,90jrong/libmesh,permcody/libmesh,jiangwen84/libmesh,karpeev/libmesh,dknez/libmesh,cahaynes/libmesh,jiangwen84/libmesh,vikramvgarg/libmesh,benkirk/libmesh,balborian/libmesh,salazardetroya/libmesh,Mbewu/libmesh,jwpeterson/libmesh,dknez/libmesh,benkirk/libmesh,friedmud/libmesh,friedmud/libmesh,BalticPinguin/libmesh,svallaghe/libmesh,karpeev/libmesh,BalticPinguin/libmesh,svallaghe/libmesh,Mbewu/libmesh,friedmud/libmesh,roystgnr/libmesh,hrittich/libmesh,pbauman/libmesh,svallaghe/libmesh,jwpeterson/libmesh,giorgiobornia/libmesh,libMesh/libmesh,permcody/libmesh,aeslaughter/libmesh,hrittich/libmesh,libMesh/libmesh,svallaghe/libmesh,salazardetroya/libmesh,dschwen/libmesh,dschwen/libmesh,benkirk/libmesh,dmcdougall/libmesh,friedmud/libmesh,salazardetroya/libmesh,libMesh/libmesh,jwpeterson/libmesh,permcody/libmesh,jwpeterson/libmesh,giorgiobornia/libmesh,capitalaslash/libmesh,karpeev/libmesh,BalticPinguin/libmesh,cahaynes/libmesh,vikramvgarg/libmesh,salazardetroya/libmesh,permcody/libmesh,capitalaslash/libmesh,dschwen/libmesh,dmcdougall/libmesh,dschwen/libmesh,jiangwen84/libmesh,benkirk/libmesh,aeslaughter/libmesh,dknez/libmesh,BalticPinguin/libmesh,Mbewu/libmesh,90jrong/libmesh,dknez/libmesh,Mbewu/libmesh,dknez/libmesh,libMesh/libmesh,coreymbryant/libmesh,vikramvgarg/libmesh,svallaghe/libmesh,pbauman/libmesh,90jrong/libmesh,cahaynes/libmesh,giorgiobornia/libmesh,roystgnr/libmesh,90jrong/libmesh,libMesh/libmesh,svallaghe/libmesh,giorgiobornia/libmesh,friedmud/libmesh,aeslaughter/libmesh,jwpeterson/libmesh,permcody/libmesh,balborian/libmesh,coreymbryant/libmesh,friedmud/libmesh,jwpeterson/libmesh,dschwen/libmesh,vikramvgarg/libmesh,pbauman/libmesh,BalticPinguin/libmesh,jiangwen84/libmesh,coreymbryant/libmesh,karpeev/libmesh,salazardetroya/libmesh,dmcdougall/libmesh,salazardetroya/libmesh,Mbewu/libmesh,permcody/libmesh,dknez/libmesh,capitalaslash/libmesh,benkirk/libmesh,libMesh/libmesh,svallaghe/libmesh,giorgiobornia/libmesh,benkirk/libmesh,jiangwen84/libmesh,friedmud/libmesh,vikramvgarg/libmesh,svallaghe/libmesh,coreymbryant/libmesh,balborian/libmesh,giorgiobornia/libmesh,pbauman/libmesh,hrittich/libmesh,coreymbryant/libmesh,dknez/libmesh,cahaynes/libmesh,jwpeterson/libmesh,aeslaughter/libmesh,roystgnr/libmesh,jiangwen84/libmesh,roystgnr/libmesh,balborian/libmesh,dschwen/libmesh,balborian/libmesh,friedmud/libmesh,aeslaughter/libmesh,capitalaslash/libmesh