[aprssig] Test program using MapSource Maps

[BH]

Just tried this in "Viewpoint" and it seems to work though it does not
give you Lat/Long as FINDU does, but you can use this to lookup
stations by Symbol, primary and secondary designation is ignored:
Earthquake symbols:
http://viewpoint.no-ip.org:8080/SymList.apl?sym=Q

Many digipeaters would be:
http://viewpoint.no-ip.org:8080/SymList.apl?sym=#

Viewpoint has a function to also lookup packet type when entering the
first character of the data portion of the packet in the callsign
slot.  Enter "$" for the callsign without quotes, would show a list of
NMEA trackers for example.   Enter ">" would show stations that have
reported a status packet.  Ditto for   the characters,   `!@$*;:)'   ,
and maybe more...