copy two unit tests from https://github.com/foursquare/fongo/issues/28
copy two unit tests from https://github.com/foursquare/fongo/issues/28

mongo-java-server was not affected since all messages (including ObjectIds)
are serialized over the wire protocol.

bwaldvogel/mongo-java-server,bwaldvogel/mongo-java-server,bwaldvogel/mongo-java-server