rust: Make private the `index` field of the `Revlog` struct To replace the previous use of this field from another module, add a `node_from_rev` method. This is the same method that already existed on `Changelog`. Differential Revision: https://phab.mercurial-scm.org/D11414

pub mod dirstate_map;
pub mod dispatch;
pub mod on_disk;
pub mod owning;
mod owning_dispatch;
pub mod path_with_basename;
pub mod status;