Gxp metadata

Add a gpx metadata parser to solve the issue #291
OK. So below, you check that `getRteptPreparedStmt() != null` before closing it. But why don't you check that `getRtePreparedStmt() != null`? Does `getRteptPreparedStmt() != null` necessarily imply `getRtePreparedStmt() != null`? That's not immediately obvious to me.