message: Remove outdated comment.
  What was decided regarding proposals with future timestamps is already
  implemented, so the TODO is outdated.
diff: @@ -935,10 +935,6 @@ impl<C: Context + 'static> SimpleConsensus<C> {
  Level::TRACE,
  "received a proposal with a timestamp slightly in the future",
  );
  - // TODO: If it's not from an equivocator and from the future, add to queue
  - // trace!("received a proposal from the future; storing for later");
  - // let timer_id = TIMER_ID_VERTEX_WITH_FUTURE_TIMESTAMP;
  - // vec![ProtocolOutcome::ScheduleTimer(timestamp, timer_id)]
  }
  let hash = proposal.hash();
  