User story #1478
Improve PB burndown on multi-projects
Product backlog burndown
- Allow render only total burndown.
- Cut burndown X sprints after total serie is finished (X is configurable) in order to avoid 1SP/Sprint series going to the infinite.
- Allow speed calculation to use all past sprints (i.e. 0 value in the plugin setting).
- Review how the speed calculation affects subproject series.