Support for composite primary keys

This is one of the several standard features that SQL supports that DGraph doesn’t. For now, one work around is to do something like this:

type Node {
  id: String!
  version: String!
  composite: String! @id

Add the composite string as id__version so that it is forced to be unique. You could use a lambda to enforce this, although if you add it correctly, it will be be unique without a lambda.