[PATCH 1 of 2] config: introduce load order tracking

[David Demelier]

On Wed, 2018-07-11 at 00:01 +0900, Yuya Nishihara wrote:
> If the problem to be addressed by this hack is important, and if the
> hack is
> really simple, sure I would say go for it. But I, as an old Mercurial
> user,
> see the bulk renaming of the config keys is minor improvement.

I think it's important, consistency in a software shows a strong core
guideline applied and strict reviewing. The current hgrc manual shows
three different styles along with unreadable names like
backgroundclosethreadcount.

Obviously my opinion is largely biased since I'm half author of the
ConfigConsolidationPlan [0].

What bothers me is that we agreed on a new syntax for new option style
[1] and it's still not applied, see server.streamunbundle and D3893.
However I think you're aware since you personally pushed my deprecated
topic.

Hopefully av6 helps me with it's reviewing :-)

[0]: https://www.mercurial-scm.org/wiki/ConfigConsolidationPlan
[1]: https://www.mercurial-scm.org/wiki/UIGuideline#adding_new_options

Regards,

-- 
David