Create extensions in the migration generator

[zachdaniel]

Right now, we create a snapshot for each resource. In order to create (and rollback) extensions in the migration generator, we will need to track another snapshot just for the repo, and we would currently only store the list of extensions. Then, when migrations are generated, we'd go through each resource in each API, grab their repo, unique them, and create snapshot for them w/ their extensions. Any extensions in the new list that aren't in the old list should be added in the generated migration.

[zachdaniel]

We can generate code something like this:

  def up do
    execute("CREATE EXTENSION \"uuid-ossp\";")
    execute("CREATE EXTENSION \"pg_trgm\";")
  end

  def down do
    execute("DROP EXTENSION \"uuid-ossp\"")
    execute("DROP EXTENSION \"pg_trgm\"")
  end

[zachdaniel]

We should consider getting a list of extensions that are installable in this way, and storing that in the repo. Then, if anything is not in the list, we can tell them to install it themselves.

[zachdaniel]

This is done.