relnotes/next

ui: refactor `readconfig()` into a form that can consume resources

The old form can't completely go away, because files outside of packages still
need to be read.  The name passed in here is a tuple of `package name, resource`
as needed by the resource API.

I like the idea of stating the config file is embedded in the executable by
listing is as `exe!package.resource`.  This would be consistent with how
`debuginstall` points to the executable for the python executable, lib, and
installed modules.  While in practice the filesystem path is available from the
backing ResourceReader when the resource is opened, it is a relative path on py2
and absolute on py3.  Further, while this would show in the `hg config` output
for each option if set as such here, it doesn't show in the `reading from...`
line when `--debug` is used.  The file isn't actually open where that prints, so
there's no way I see to get that info there.  So I opted for the simple prefix
to distinguish resources from files.

Differential Revision: https://phab.mercurial-scm.org/D7775

== New Features ==

 * Windows will process hgrc files in %PROGRAMDATA%\Mercurial\hgrc.d.


== New Experimental Features ==


== Bug Fixes  ==

 * The `indent()` template function was documented to not indent empty lines,
   but it still indented the first line even if it was empty. It no longer does
   that.

== Backwards Compatibility Changes ==


== Internal API Changes ==

 * Matcher instances no longer have a `explicitdir` property. Consider
   rewriting your code to use `repo.wvfs.isdir()` and/or
   `ctx.hasdir()` instead. Also, the `traversedir` property is now
   also called when only `explicitdir` used to be called. That may
   mean that you can simply remove the use of `explicitdir` if you
   were already using `traversedir`.

 * The `revlog.nodemap` object have been merged into the `revlog.index` object.
   * `n in revlog.nodemap` becomes `revlog.index.has_node(n)`,
   * `revlog.nodemap[n]` becomes `revlog.index.rev(n)`,
   * `revlog.nodemap.get(n)` becomes `revlog.index.get_rev(n)`.