Add support for space-track.org in TLE Network Update

[marsfan]

space-track.org is a database maintained by the United States Space Force of all (non-classified) objects that the USSF is currently tracking. Access is allowed for the general public, but requires creating a login, therefore a simple URL cannot be used to allow network updating. However, there is a REST API to allow downloading data from the database.

Adding support for using this API to access the space-track database will allow users to greatly expand the number of supported satellites in GPredict, without having to manually update the TLEs

[csete]

It is on the TODO list for a future update

[weather-tracker]

that will be nice

[weather-tracker]

this looks helpful https://www.space-track.org/documentation#howto-api_cplusplus https://www.space-track.org/documentation#howto-api_curl