This adds two columns to the `recording_session` table. One column is a
foreign key to the `iam_user_hst` table and the other is a foreign key
to the `iam_scope_hst` table. The foreign key to the `iam_scope_hst`
table reference the IAM scope the user belongs to at the time of the
recording.
Michael Gaffney
882b7eca2f