Allow release milestones to be shown in the calendar view as a vertical line Merged

We have, for example, code freeze as a major milestone for our releases. It would be nice if it could show as a vertical line in the calendar view so we can visually line up all the features that must be done prior to that line. It would give me an easy, visual way to find a feature that would go past the code freeze date and then move it to the next release.