Ability to group keyframes and move them as a group

[f-michaut]

This would be useful when placing time and position keyframes together, but moving them later
Or to change the path in the middle of a replay without affecting the end of the replay.

For instance, if I want to shorten a sequence on the timeline in the middle of the replay, I can do it, but then I will need to move EVERY keyframe after that of EXACTLY the delta time that I removed from the middle of the clip.

If I could simply make a group, and drag the whole group (or enter a timestamp for the whole group) this would ensure that I don't break the timings between the keyframes of that group and have the ability to make adjustments to it's position on the timeline