change default guesses to 'moments' to match old behavior.  Why didn't I do this before/
change default guesses to 'moments' to match old behavior.  Why didn't I
do this before/

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