Move Jackson ObjectId detection into a dedicated class

refs #82
Relax JacksonObjectIdUpdater's methods visibility

refs #82
Convert ObjectIdUpdater to a class an inject Jackson stuff
Convert ObjectIdUpdater to interface again
Rename ObjectIdUpdater methods

Public API
Add ReflectiveObjectIdUpdater and allow customization by injection
Merge pull request #103 from bguerout/features/enhance-objectidupdater

Add reusable ReflectiveObjectIdUpdater