D7909: rust-filepatterns: add support for `ignore` and `subignore` patterns

[Alphare (Raphaël Gomès)]

Alphare added a comment.


  Note to reviewers: this stack is part of the larger series of getting a full Rust dirstate.status which is most of the performance hit in bare hg status. More patches are coming, but I figured I would send the patches as I go to help with review timing.

REPOSITORY
  rHG Mercurial

CHANGES SINCE LAST ACTION
  https://phab.mercurial-scm.org/D7909/new/

REVISION DETAIL
  https://phab.mercurial-scm.org/D7909

To: Alphare, #hg-reviewers
Cc: durin42, kevincox, mercurial-devel