In Roadmap, offer Sprints as columns and show Child-issue assigned to sprints like GANTT

Roadmap view is useful to see the association of child-issues (stories, tasks) to Epics, and to see the association of Epics with time periods (calendar months, weeks, or days).

However, in KANBAN process, the main unit of time for planning purpose is the SPRINT.

Also, Epics may span multiple sprints, and the current Roadmap does not visually show to which sprint (or sprints) a child issue has been assigned.

As a user, in the Roadmap view, I want to be able to select SPRINTS (in addition to month, week or day) as unit of time, and then to be able to assign the child issues (stories and tasks) to those sprints within the roadmap view.

Ideally, I'd like the association of child issues to sprints to be shown on the roadmap view in the form on rectangles, like a GANTT chart (as is currently already displayed for the Epics)

Ideally, I'll like those child-issue rectangles to have a progress bar, with colors corresponding to issue statuses (in the same way that progress bars are already shown for Epics).  That way, I could see at a glance how and Epic is progressing and can visually see when a child issue that was supposed to be completed in a single sprint ended up needing to be assigned to multiple sprints.

These changes would make the Roadmap view correspond to the way I plan for projects:

• First I figure out the Epics I need to pursue to accomplish the business objectives
• Second I figure out the stories and task required to achieve the Epic
• Third I figure out how Epics lay out over time, based on my customers' priorities and the logical sequence of development and dependencies
• Fourth, I figure out how the stories and tasks can be assigned to sprints (at least for the next few sprints)
• Then, after each sprint, I adjust the plan based on what I learned and what was actually completed during prior sprint.