phases: track phase changes from 'retractboundary'
We adds new computation to find and record the revision affected by the
boundary retraction. This add more complication to the function but this seems
fine since it is only used in a couple of rare and explicit cases (`hg phase
--force` and `hg qimport`).
Having strong tracking of phase changes is worth the effort.
Mercurial
=========
Mercurial is a fast, easy to use, distributed revision control tool
for software developers.
Basic install:
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
Running without installing:
$ make local # build for inplace usage
$ ./hg --version # should show the latest version
See https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.