merge from distance_rings branch. also added km.
merged from branch flight_timer. needs testing
now same frequenceis are merged
added KML from tracks branch
added KML from tracks branch
misc small fixes
removed seconds from the hobbs timer
Completed merge change for flight tracks.
Removed some configuration options to make it less busy.
added 4th ring
merged from DistanceRingsV2
Change the scaling threshold values to better align to the static rings at the default zoom factor.
drawing tracks with shape instead of calling new and re-implementing the shape code
Merge branch 'master' of https://github.com/apps4av/avare
fixed a crash with distance ring
Merge branch 'master' into awosInAfd