Support vector arguments with offset in scan kernels.

See merge request inducer/pyopencl!47

This reverts commit ea24cc51.

This reverts commit 749e6a3e.

Fix bank conflict avoidance

See merge request !46

Fix, test cl{Compile,Link}Program wrappers

See merge request inducer/pyopencl!45

Pybind11

See merge request !44