Summary:
Pull Request resolved: https://github.com/facebookincubator/ent/pull/140
This part of the effort of moving logic from Go templates to shared packages.
Next diffs will migrate the neighbors-set and predicates as well.
Dedicated tests for `sql/dialect/graph.go` will be added in a follow-up diff.
Reviewed By: alexsn
Differential Revision: D18304531
fbshipit-source-id: 93e9cf2636b5b4525eb27305bd2708122cfd6e40
