windows: add a global equivalent to /etc/mercurial for *.rc processing
This follows the Unix model of processing this directory immediately after
<internal>/*.rc, and prior to the installation relative files. Since the Unix
processing supports both a directory and a file (the former overriding the
latter), and since %HOME% supports both `*.ini` and `.hgrc` (again, the former
overriding the latter), this does too. The Unix file doesn't have a `.` prefix,
so it's not used here either.
Note that this is the opposite order of processing the exe relative paths. But
since it's in agreement with Unix, %HOME% and %USERPROFILE%, it seems reasonable
to ignore that. Maybe we can change that and take a BC, because that's
something the installer should be controlling, and I can't imagine people having
both paths *and* conflicting settings.
Differential Revision: https://phab.mercurial-scm.org/D7692
$ hg init repo
$ cd repo
$ touch foo
$ hg ci -Am 'add foo'
adding foo
$ hg up -C null
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
this should be stored as a delta against rev 0
$ echo foo bar baz > foo
$ hg ci -Am 'add foo again'
adding foo
created new head
$ hg debugindex foo
rev linkrev nodeid p1 p2
0 0 b80de5d13875 000000000000 000000000000
1 1 0376abec49b8 000000000000 000000000000
$ cd ..