D8030: uncopy: add support for unmarking committed copies

[durin42 (Augie Fackler)]

durin42 added a comment.


  I'm conflicted on rolling the `uncopy && amend` action into the uncopy command like this. Could users not (without this patch) do `hg uncopy foo && hg amend`?

REPOSITORY
  rHG Mercurial

CHANGES SINCE LAST ACTION
  https://phab.mercurial-scm.org/D8030/new/

REVISION DETAIL
  https://phab.mercurial-scm.org/D8030

To: martinvonz, #hg-reviewers
Cc: durin42, mercurial-devel