Compute detailed relationship type from WHERE clause

[pstutz]

https://github.com/opencypher/cypher-for-apache-spark/blob/3afbaabb55d6ec808e7b181f80911e332fef8aa1/src/test/scala/org/opencypher/caps/ir/impl/block/TypedMatchBlockTest.scala#L47

[boggle]

Move to trello

[Mats-SX]

These should be able to have the same plan:

it("should plan efficiently") {
  val given = initGraph("CREATE ()-[:FOO]->()-[:BAR]->()")

  PrintRelationalPlan.set()

  given.cypher(
    """
      |MATCH ()-[r]->()
      |WHERE type(r) = 'FOO'
      |RETURN r
    """.stripMargin).show
  
  given.cypher(
    """
      |MATCH ()-[r:FOO]->()
      |RETURN r
    """.stripMargin).show
}