uncommit: don't allow dirty working copy with PATH (issue5977)
On a dirty PATH, uncommit was working without even setting the config
experimental.uncommitondirtydir to True. Ideally, it should abort
as it does for a dirty dir. This patch makes uncommit to require the
config option experimental.uncommitondirtydir on a dirty PATH.
Original patch to evolve extension authored by Dan Villiom Podlaski Christiansen:
Differential Revision: https://phab.mercurial-scm.org/D5940