Remove dead code about native serializer
a test case for saving documents shaped like map reduce results for issue #189
corrected formatting
No longer put _id into DBObject during insert
Merge branch 'feature_composite-key' of github.com:ctrimble/jongo into ctrimble-feature_composite-key
Marshall _id when id is a complex type

refs #189
refs #190
Move complex id marshalling into custom DBObject

refs #189
refs #190
Remove deprecated ObjectId.massageToObjectId usage
Merge branch 'feature_composite-key' of github.com:ctrimble/jongo into ctrimble-feature_composite-key