manifest: remove addgroup() from manifestlog and imanifestlog addgroup() is part of the storage interface for manifests. Unfortunately, we don't yet have a formal storage interface for manifests. (One will be established in subsequent commits.) One thing is for sure, addgroup() doesn't belong on imanifestlog - at least not unless we extend that interface to encompass storage. For now, let's access addgroup() on the _revlog attribute, just like we do for tree manifests. Even though this violates visibility, it is consistent. Differential Revision: https://phab.mercurial-scm.org/D4274

repository: clarify role of imanifestlog Looking at the implementation of manifest.manifestlog, it is highly tailored towards servicing the root manifest. So clarify that in the interface docstring. Differential Revision: https://phab.mercurial-scm.org/D4273

changegroup: change topics during generation Changegroup generation and consumption currently uses different sets of topics. Generation uses "bundling" and consumption uses the name of the thing being consumed. This commit makes the topic and unit names consistent on both ends. The reason I chose to change the generation side is because when "bundling" is used for 3 different stages, it is unclear which stage of changegroup generation we're in. By making the topics "changesets," "manifests," and "files," one can get a better feel for how far along in the bundling process we are. Differential Revision: https://phab.mercurial-scm.org/D4272

changegroup: rename mfs to manifests In the name of readability. Differential Revision: https://phab.mercurial-scm.org/D4271