Switch tov2 items

This branch completely switches Item updates (not listing updates) to the official GW2 API v2.

I also took the liberty to remove the classes associated with the ItemDB-Queue as it is not needed anymore. I hope I did not overlook any references.

The scripts called in the `daemons` directory now output an error message and exit with code 1 if they are called. That way no cron job or other automated call should slip past.