help: update the default value specified for `profiling.time-track` I tried conditionalizing this in a `.. container::` block, but that seemed to add an extra blank line between the main text and the parenthetical.

profiling: revert the default mode back to 'cpu' on Windows On Windows, os.times() only returns user and system times. Real elapsed time is 0. That results in no actual times reported, an end wall time of 0.000000, and seemingly randomly sorted stack frames. This at least provides test stability in test-profile.t. I kind of think that `default=pycompat.iswindows and 'cpu' or 'real'` would be a better way to set the default in configitems, but I didn't see any other examples of this, and thought maybe there's a reason for that. That might allow plugging the value into the help text automatically- the documented default wasn't updated in db0dba2d157d.

phase: add an archived phase This phase allows for hidden changesets in the "user space". It differs from the "internal" phase which is intended for internal by-product only. There have been discussions at the 4.8 sprint to use such phase to speedup cleanup after history rewriting operation. Shipping it in the same release as the 'internal-phase' groups the associated `requires` entry. The important bit is to have support for this phase in the earliest version of mercurial possible. Adding the UI to manipulate this new phase later seems fine. The current plan for archived usage and user interface are as follow. On a repository with internal-phase on and evolution off: * history rewriting command set rewritten changeset in the archived phase. (This mean updating the cleanupnodes method). * keep `hg unbundle .hg/strip-backup/X.hg` as a way to restore changeset for now (backup bundle need to contains phase data) * [maybe] add a `hg strip --soft` advance flag (a light way to expose the feature without getting in the way of a better UI) Mercurial 4.8 freeze is too close to get the above in by then. We don't introduce a new repository `requirement` as we reuse the one introduced with the 'archived' phase during the 4.8 cycle.