Merge pull request #8 from valeriysokolov/master

create_sino uses proj_geom and vol_geom on GPU, without projector
Fix version check for cython nightly builds.
Merge pull request #10 from kalvdans/master

Fix version check for cython nightly builds.
Use floats during volume geometry creation
Added move_vol_geom helper function to move center of volume geometry
Merged conflicts.