Revert "Package-Requires: add emacs-23.2"

This reverts commit 3f2f81b347bff884ad4759ed4c8b12c204ce75e0.

No version of `package.el' which works with Emacs 23.x
understands the "emacs" virtual package.  See issue #1369.
respect default-directory when creating and following xrefs
Declare debug information for some macros.
create and follow xrefs in log buffers too

Only do so in `magit-log-mode' and `magit-reflog-mode'
buffers; in `magit-log-select-mode' buffers don't do so.
Merge pull request #1370 from vanicat/t/declare-debug

Declare debug information for some macros.
Merge branch 'master' into next

Conflicts:
	magit.el
magit-read-gpg-secret-key: don't require match

Let the user exit with any input.  This allows selecting a subkey,
even though we don't offer such keys for completion.
Merge branch 'master' into next

Conflicts:
	magit.el