Reverting a merge request should revert the commits in the way they were merged

Problem to Solve

The ability to revert a merge request is only available when using a merge commit strategy. Even if you're using semi-linear with a merge commit the revert MR only reverts the merge commit and not the individual commits.

This leaves a harder to follow and inconsistent history as to what commits have been added and removed in a project.

Proposal

Revert support should be extended to match the style of merge that the changes were added with. This means if you merge with fast forward, a revert should be possible that reverts each commit individually from a merge request. Similarly if you're using a semi-linear with merge then we should revert the individual commits and the merge commit.