Mercurial native mode: transitional support for Tree and Blob
In this Merge Request, we are diverting the methods dealing with Git trees and blobs to the inner Git repository, and back-converting what needs to be in order to reference only Mercurial changeset IDs in the Commit
objects.
Natively dealing with trees and blobs will be the main topic of %HGitaly2: fully native (but not the only one). In other words, this is to be considered scaffolding and should be present for a few months at most.