Narrow columns used in list_revoked_tokens sql

Currently the SQL backend lists revoked tokens by selecting all of the
columns, including the massive "extra" column. This places a significant
burden on the client library and wastes resources. We only need the
id/expired columns to satisfy the API call.

In tests this query was several orders of magnitude faster with just two
thousand un-expired revoked tokens.

Change-Id: I04d62b98d5d760a3fbc3c8db61530f7ebccb0a48
Closes-Bug: #1253755
Merge "Narrow columns used in list_revoked_tokens sql"