Patched out issue where the script would cause client disconnects

Prev. patch synced gps to server, but when gps were removed they were only removed on client. This causes server to keep a permanent history of every thermal signature you've seen, and redisplays it to you when you relog

- Disables cross sector sync (so I can finish last pieces of testing without harassing server)
- Added cleanup for synced gps (since some players reported them getting stuck in their list)
- Signatures only show up after broadcasting 15km instead of 1km
- Made thermal scan gps sync with server (was only creating on client before, which is why cross sector sync was broken)