Only read .hg/hgrc files from trusted users/groups
The list of trusted users and groups is specified in the [trusted]
section of a hgrc; the current user is always trusted; "*" can be
used to trust all users/groups.
Global hgrc files are always read.
On Windows (and other systems that don't have the pwd and grp modules),
all .hg/hgrc files are read.
This is essentially the same patch that was previously applied as
revision 494521a3f142.
#!/bin/sh
echo "[extensions]" >> $HGRCPATH
echo "mq=" >> $HGRCPATH
hg init a
cd a
echo 'base' > base
hg ci -Ambase -d '1 0'
hg qnew -mmqbase mqbase
hg qrename mqbase renamed
mkdir .hg/patches/foo
hg qrename renamed foo
hg qseries
ls .hg/patches/foo
mkdir .hg/patches/bar
hg qrename foo/renamed bar
hg qseries
ls .hg/patches/bar
hg qrename bar/renamed baz
hg qseries
ls .hg/patches/baz