bugfix: xmin:xmax didn't reset fitregion in selectregion code
bugfix: xmin:xmax didn't reset fitregion in selectregion code

jpinedaf/pyspeckit,vlas-sokolov/pyspeckit,jpinedaf/pyspeckit,low-sky/pyspeckit,keflavich/pyspeckit,bsipocz/pyspeckit,e-koch/pyspeckit,dinossimpson/pyspeckit,dinossimpson/pyspeckit,allisony/pyspeckit,mikelum/pyspeckit,pyspeckit/pyspeckit,keflavich/pyspeckit-obsolete,keflavich/pyspeckit,allisony/pyspeckit,bsipocz/pyspeckit,e-koch/pyspeckit,low-sky/pyspeckit,vlas-sokolov/pyspeckit,pyspeckit/pyspeckit,mikelum/pyspeckit