rust: iterator bindings to C code
In this changeset, still made of Rust code only,
we expose the Rust iterator for instantiation and
consumption from C code.
The idea is that both the index and index_get_parents()
will be passed from the C extension, hence avoiding a hard
link dependency to parsers.so, so that the crate can
still be built and tested independently.
On the other hand, parsers.so will use the symbols
defined in this changeset.
## What is it?
This extension adds ability to save certain pushes to a remote blob store
as bundles and to serve commits from remote blob store.
The revisions are stored on disk or in everstore.
The metadata are stored in sql or on disk.
## Config options
infinitepush.branchpattern: pattern to detect a scratchbranch, example
're:scratch/.+'
infinitepush.indextype: disk or sql for the metadata
infinitepush.reponame: only relevant for sql metadata backend, reponame to put in
sql
infinitepush.indexpath: only relevant for ondisk metadata backend, the path to
store the index on disk. If not set will be under .hg
in a folder named filebundlestore
infinitepush.storepath: only relevant for ondisk metadata backend, the path to
store the bundles. If not set, it will be
.hg/filebundlestore