Update neighborlist to build in double precision
Update neighborlist to build in double precision

I Did this the lazy way by turning tex fetches into global mem reads. I will revisit the peformance implications of that later. Right now, just trying to get it to compile again.

refs #1035
joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue