[md][glue] Fixes change that changed the orientation of inside/outside

To make the interface more clear this commit introduces a new intersection interface and deprecates the old one.

The old inside(n) is replaced by targetEntity(n) The old outide(n) is replaced by domainEntity(n) The old neighbor() is replaces by numTargetNeighbors()/numDomainNeighbors().

Furthermore num{}Neighbors returns 1 if the {}-dimension is smaller than the other dimension.