D7809: revlogutils: move the NodeMap class in a dedicated nodemap module

[martinvonz (Martin von Zweigbergk)]

martinvonz added a comment.


  We recently gained a `mercurial.utils` module. Should `mercurial.revlogutils` become `mercurial.utils.revlogutil` instead?

REPOSITORY
  rHG Mercurial

CHANGES SINCE LAST ACTION
  https://phab.mercurial-scm.org/D7809/new/

REVISION DETAIL
  https://phab.mercurial-scm.org/D7809

To: marmoute, indygreg, #hg-reviewers
Cc: martinvonz, mercurial-devel