Add replication refs-filtering before push

Add ability to filter out refs before being pushed for replication to
remote instance. This will help to prevent split-brain issue by
allowing us to create filter in multi-site plugin to stop the out of sync
instance from overriding the changes of the instance that is up to date.

Bug: Issue 11175
Change-Id: I99a7cb4fb2f231626d50abc7d90bb3d79c23861a