hack when couch error occurs.

Due to following issue. Error handler crashes. However, it seems data actually gets inserted although it get the error. [{'reason': '{exit_status,0}', 'id': '8b5abd973a55d41376f5b2f32b02d2df', 'error': 'os_process_error'}]
https://issues.apache.org/jira/browse/COUCHDB-893