updated the zerg90 public safety map for Worcester County Mass

https://www.google.com/maps/d/edit?mid=1WSHNxrVCSj3AwJQlHfAAdiVsuno&usp=sharing

added MedStar Amb Sta in Worcester on the SW Cutoff

added more ambulances to the ambulance layer - need to check the
statewide ambulance map for more sites