Fix MG base layer group toggling from legend not updating the map
Fix MG base layer group toggling from legend not updating the map

Fixes #84

jumpinjackie/mapguide-react-layout,jumpinjackie/mapguide-react-layout,jumpinjackie/mapguide-react-layout,jumpinjackie/mapguide-react-layout,jumpinjackie/mapguide-react-layout