Made it so config file need not contain all possible elements of cfgDefaults.
Made it so config file need not contain all possible elements of cfgDefaults.

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