Graph v1 marks branchpoint as initial commits

[proski]

Graph v1 uses the initial commit symbol for all branchpoints. Graph v2 uses that symbol only for the first commit in the repository. That's inconsistent. I believe the graph v2 behavior is more reasonable and graph v1 should be changed to match. It's also possible to have a separate boolean flag for branchpoints, but I don't feel it would be a significant enhancement.

Graph v1:

Graph v2: