Implement code to acknowledge opt_out users/stations

[interplanetarychris]

In order to prevent re-processing of data for Stations (users) who have opt-ed out of TruSat, a number of enhancements should be implemented to prevent this data from being processed in TruSat.org and potentially other future decentralized implementations.

At present, this would appear to apply to:

1. SQL Station Table (a place to store the flag per station)
2. addParsedIOD() - Check for flagged stations before submitting
3. Any queries which JOIN with the Station table - the station_num will need to be stored, but location data will be nulled out (currently a bug that needs to be filed). This is probably not an issue because there will also be no ParsedIOD records for the station.

If the data is manually removed from the database, this should prevent re-introduction of the data in future import sessions.