Add equal?/2 and embed_as/1 Ecto.Type callbacks to Waffle.Ecto.Definition

[yunmikun2]

equal?/2 callback is required for an Ecto.Type since Ecto 3.0.0 and embed_as/1 -- since Ecto 3.2.0. Lacking to provide these callbacks raises a warning while compilation in user's code.

[yunmikun2]

Sorry, my mistake, these callbacks are defined automatically on use Ecto.Type. Closing this now.