constants, throw FatalExceptions on DB errors, option for getDbh() to
rethrow the PDO exception (when checking for tables), removed created_at
and updated_at fields from the users table, removed other methods not
part of the interface (GetUserDevicePermission, GetMappedUsername,
MapUsername and UnmapUsername - code will be attached to the ticket),
renamed and fixed CheckTablesHaveData so it indicates if there is data
in any table, included sql stuff to composer autoload, tweaked the
output of the migration script, don't log GetStateHash() as it logs a
lot.

Released under the Affero GNU General Public License (AGPL) version 3.