bundle: consistently keep a list of stringified revisions in "revs" Before this patch, "revs", in the "not base" branch, would be a list of mixed integral revnums, hex nodeids, and branch names. After this patch, they're all strings. They can still be a mix of hex nodeids and branch names, but the important thing for my future patches is that they're consistently in string form. Differential Revision: https://phab.mercurial-scm.org/D3049