D245: obsstore: rename precursors into predecessors

[dsp (David Soria Parra)]

dsp added inline comments.

INLINE COMMENTS

> obsutil.py:210
>      nm = unfi.changelog.nodemap
> -    precursorsmarkers = unfi.obsstore.precursors
> +    precursorsmarkers = unfi.obsstore.predecessors
>      successormarkers = unfi.obsstore.successors

should this be called `predecessormarkers`?

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D245

To: lothiraldan, #hg-reviewers
Cc: dsp, mercurial-devel