bundle2: pass the operation source down to the changegroup This is currently not used by anything in core (and redundant with the url), the real source information is much more useful. This is going to be used in sidedata exchange patches coming soon. Differential Revision: https://phab.mercurial-scm.org/D9986

gendoc: use an empty comment so aliases are separated from previous elements For commands like `hg bookmarks`, where there's no `[+] marked option can be specified multiple times`, this causes the final option in the option list to not be the parent of the aliases definition. The aliases section is thus marked as a blockquote like on commands that do have text separating the option list and the aliases definition. Differential Revision: https://phab.mercurial-scm.org/D9990

gendoc: add support for loading extensions from config settings We manage our installation and ship some extensions, enabled by default for our users, that are in hgext3rd or other directories not scanned by this tool by default. We want to generate docs during the build process, and having those docs include the extensions that users don't have to manually enable is desirable. This is *not* desirable for the normal build process, however, and should never be enabled by default. Differential Revision: https://phab.mercurial-scm.org/D9989