Leave red dots path and center on first plane detected

[guerrerocarlos]

• Fixes Google Maps API error,

• Adds a red dot on each detected position, effectively making each plane to leave a trace in the map.

• Over time, gives you a sense of the area detected by your antenna:

• Centers the map automatically on the first plane detected.

[guerrerocarlos]

• Changes color of the path depending on altitude to better visualize path.