On server incident refresh, remove old markers before adding new dones
On server incident refresh, remove old markers before adding new dones

Otherwise, you end up with multiple copies and very dark markers.
https://github.com/e-mission/e-mission-phone/pull/263#issuecomment-322669042

e-mission/e-mission-phone,shankari/e-mission-phone,e-mission/e-mission-phone,shankari/e-mission-phone,e-mission/e-mission-phone,e-mission/e-mission-phone,shankari/e-mission-phone,shankari/e-mission-phone