Implement _replicator database

[mschoch]

Need to implement the _replicator database. Ideally the implementation should be structured similar to the iOS version.

[pramodshri]

Any ideas when this will be implemented?

[mschoch]

probably still weeks/months out. my time is limited and i have a bunch of other changes to the replicator that have to get merged first.

[jchris]

This is not a blocker right now, so let us know if you hit any issues.

[tleyden]

This will affect phonegap api users, since inconsistent betweeen ios and android