ios: Changed distanceFilter from none to 5 meters, prevents it from spamming the callback even though nothing changed.

close #16
Merge branch 'master' of https://git-wip-us.apache.org/repos/asf/cordova-plugin-geolocation
Merge branch 'master' of ssh://github.com/ldeluca/cordova-plugin-geolocation into CB-6127cordova-plugin-geolocation