Ability to delete all branches that have been merged since a given date

Description

At the moment we have a Delete button to delete all the branches that have been merged to master.

However, this action is all or nothing. What if we could only delete branches older than a specific date to allow a fine grain management of the branches? Companies might want to keep at least one year of branches, merged or not, in their projects, and remove the rest.

Description

• When clicking on the Delete merged branches button, display a panel asking
  • Delete all the branches
  • OR
  • Delete all branches before DATE