update wcs when slicing cubes
update wcs when slicing cubes

jpinedaf/pyspeckit,low-sky/pyspeckit,pyspeckit/pyspeckit,keflavich/pyspeckit,e-koch/pyspeckit,pyspeckit/pyspeckit,allisony/pyspeckit,e-koch/pyspeckit,vlas-sokolov/pyspeckit,allisony/pyspeckit,keflavich/pyspeckit,vlas-sokolov/pyspeckit,jpinedaf/pyspeckit,low-sky/pyspeckit