rust-status: fix thread count ceiling This was forcing 16 threads instead of creating a ceiling, which is wrong when either the available parallelism of the platform is lower or when the user wants to set it explicitly (like we do in `run-tests.py`)

amend: add a --draft option to set phase to draft Some users create commits in secret phase by default and then want to make them draft so they can be uploaded. This patch adds a --draft option for that. We already have a flag for changing the phase to secret, so it seems consistent to have one for draft.

commit: add --draft option to use draft phase

tests: use graph log in test-phases.t It's hard to tell that the phases are ordered correctly without seeing the graph.

commit: move check for incompatible args earlier I think it makes sense to check the command line arguments as early as possible, so we don't have to wait for a repo lock to tell the user that they passed invalid arguments.

delta-find: add a delta-reuse policy that blindly accepts incoming deltas When this policy is set, incoming deltas are blindly accepted without regard for the validity of the chain they build.

delta-find: add a `delta-reuse-policy` on configuration `path` That option allows to control the behavior on a per-path basis, opening the way to treating pulls from central servers differently than other operations.

changegroup: add `delta_base_reuse_policy` argument The argument available through function from changegroup.apply to `revlog.apply` allow to override the revlog configuration in terms of delta-base-reuse policy when searching for a delta to store a revision. It will be put to use in the next changesets.

bundleoperation: optionnaly record the `remote` that produced the bundle We have the information at hand, and the peer now have knownledge of its `path` object, which constaints useful behavior configuration. So the simpler seems to be to pass that object around so it can be used if needed.

delta-find: add a test checking various simple behavior There are enough work happening in this area that it is worth having a dedicated test for it. So far we add to small test checking that the "best" parent is picked as the delta base and that this behavior can be controlled during commit and unbundle.