CBL - Map a Local Collection to a Different One on Remote

https://docs.couchbase.com/sync-gateway/current/sync-inter-syncgateway-overview.html#active-to-active-mobile-synchronization

From Ben Brooks:
Not sure whether it's worth describing here (or elsewhere) about how you can map a local collection to a different one on the remote.

You do this by specifying sets of collections that are used as a map:
`collections_local: [a, b, c]` replicates a, b, c
`collections_remote: [z, x, y]` maps collections to these alternatives on the remote

https://issues.couchbase.com/browse/CBG-2320

The PRD has some more detail about mapping.

Under the heading "Mapping Source and Target Collections"

https://docs.google.com/docum…ading=h.811eqtvhkn2g

To summarise, it is a way of replicating documents in one scope.collection to a scope.collection of a different name on the target.