[PATCH 1 of 9] config: register the 'devel.all-warnings' config

[Pierre-Yves David]

# HG changeset patch
# User Pierre-Yves David <pierre-yves.david at octobus.net>
# Date 1498648780 -7200
#      Wed Jun 28 13:19:40 2017 +0200
# Node ID 8e4ad21630cd8491527bcc0cc7a5b517e41f8f0a
# Parent  78fc540c53e1ee7d3dc6dc7e32b739ce2dfeebf8
# EXP-Topic config.register
# Available At https://www.mercurial-scm.org/repo/users/marmoute/mercurial/
#              hg pull https://www.mercurial-scm.org/repo/users/marmoute/mercurial/ -r 8e4ad21630cd
config: register the 'devel.all-warnings' config

Let us start registering the existing option. I'm starting with the 'devel'
section because it is full of useful things that are poorly documented. So
registering these will more than other section.

diff --git a/mercurial/configitems.py b/mercurial/configitems.py
--- a/mercurial/configitems.py
+++ b/mercurial/configitems.py
@@ -56,6 +56,9 @@ def getitemregister(configtable):
 
 coreconfigitem = getitemregister(coreitems)
 
+coreconfigitem('devel', 'all-warnings',
+    default=False,
+)
 coreconfigitem('patch', 'fuzz',
     default=2,
 )