Burndown chart by team

• We need some concept of teams. (Maybe a type of groups?)
• We need some concept of associating/assigning teams to issues.
• If we have these two components, then we would be able to view burndown charts by teams. I.e. it would filter the chart to be applicable to issues that are associated with that team.
• We could have a feature to have burndown chart filter by label, but that means if later on, if we move into teams, we would have to re-invent the filtering again to include teams.
• So better to start with a teams filter first, and focus on that.