make mercurial look in more places for config files. now it searches <install dir>/etc/mercurial, /etc/mercurial, and user hgrc. this allows site-wide configuration to be shared over automounted nfs partition, instead of chenging on every system. option of having local configuration on every system remains. old code for searching /etc/mercurial/hgrc.d never worked, this code is tested and works.

#!/bin/sh

mkdir t
cd t
hg init
echo a > a
hg add a
hg commit -m test -d "0 0"
hg history
hg manifest
hg cat a
hg verify