removing lanthanum from autopart

Change-Id: Id216962aeabcb6290d2a315b7f5d31d729da032c
Drop unsupported write concern parameter from MongoDB URI

The 'w' parameter in connection URIs specifies the king and level of write
concern that the MongoDB driver should use. See:
<http://docs.mongodb.org/manual/reference/connection-string/#connections-connection-options>

It is not supported by the version we are running, though, so I'm removing it
for now.

Change-Id: I98c42082c0d4dcd6e5fc8755eeca6535d395e2da
Merge "removing lanthanum from autopart" into production