title: git --no-replace-objects ineffective when changing submodule ref
body: <p>I have super-repo/submodule structure where some submodules need to be migrated to another upstream source. The submodule itself is using git-replace internally in order to mimick the behavior of the old upstream source (git histories are unrelated but the replace refs ensure that old commits can be found).</p>
  <p>What I could not achieve is easy editing of the super repo in cases where I want to migrate an existing branch there at once to point to the new refs. However, doing that without new commits on the submodule!</p>
  <p>When I do a <code>git add smfolder</code> there, nothing happens. git seems to assume that the SM is unchanged. And it might look unchanged but the reference stored in super-repo is still the old one, and I wish to convert it to a new one.</p>
  <p>I have even tried <code>git --no-replace-objects add smfolder</code> following git-replace manpage. This is also not effective. What else can I use to overcome this shadowing from git-replace?</p>