* Add APRS device tracker component
This component keeps open a connection to the APRS-IS infrastructure so
messages generated by filtered callsigns can be immediately acted upon.
Any messages with certain values for the 'format' key are position
reports and are parsed into device tracker entities.
* Log errors and return if startup failure
* Fix unit tests
Fabian Affolter
Paulus Schoutsen
Franck Nijhof
Franck Nijhof
Philip Rosenberg-Watt