config: add a .hg/hgrc-not-shared which won't be shared in share-safe mode
Previous patches add a safe mode for sharing repositories which involve sharing
of source requirements and config files.
In certain situations we might need to add a config to source repository which
we does not want to share. For this, we add a .hg/hgrc-not-shared which won't
This also adds a --non-shared flag to hg config command to see the
Differential Revision: https://phab.mercurial-scm.org/D8673