Added resetMarkerGroup and resetMarkerGroups function to leafletMarkersHelpers as fix/workaround for #381.
Initial go at supporting marker group options.
Updated bower.json
Merge branch 'Feature_MarkerGroupOptions'
Merge branch 'master' of https://github.com/code4sac/angular-leaflet-directive into code4sac-master

Conflicts:
	dist/angular-leaflet-directive.js
	dist/angular-leaflet-directive.min.js
Merge branch 'code4sac-master'