D2701: merge: use constants for actions

[phillco (Phil Cohen)]

phillco added inline comments.

INLINE COMMENTS

> merge.py:909
>      if actions:
>          # k, dr, e and rd are no-op
> +        for m in (ACTION_ADD, ACTION_ADD_MODIFIED, ACTION_FORGET, ACTION_GET,

Update this too?

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D2701

To: indygreg, #hg-reviewers, phillco
Cc: phillco, pulkit, mercurial-devel