path: update `get_unique_pull_path` to point out it returns a url Unlike other functions in this module it returns a url as `bytes` and not a `path` object. Let us point it out in the doc.

changelog-v2: fix the docket `struct` The previous definition used `L` which is actually 4 bytes, while the documentation and intend was to use `Q`, i.e. 8 bytes.

path: pass `path` to `peer` in infinite push We directly use the `path` object to build the `peer` object.

path: pass `path` to `peer` in `hg histedit` We directly use the `path` object to build the `peer` object.

path: pass `path` to `peer` in the `outgoing` revset We directly use the `path` object to build the `peer` object.

path: pass `path` to `peer` in `hg summary` We directly use the `path` object to build the `peer` object.

path: pass `path` to `peer` in `hg outgoing` We directly use the `path` object to build the `peer` object.

path: pass `path` to `peer` in `hg bundle` We directly use the `path` object to build the `peer` object.

path: have `peer` constructor accept a `path` object We don't do anything fancy with it yet, but this is an important step towards having the peers aware of their "source" and associated configurations.

path: deprecated the `pushloc` attribute We want to make sure people with use the full featured path "variant".