Add SPDX-License-Identifier headers

Add SPDX-License-Identifier headers to all substantial source files.
Collapse copyright years.  Add some Emacs configuration for files
where the copyright notice is at the end.  Add a test that every
file has SPDX-License-Identifier.

1 files changed, 2 insertions, 2 deletions

diff --git a/examples/stanford.conf b/examples/stanford.conf
index b4cd65a..697342b 100644
--- a/examples/stanford.conf
+++ b/examples/stanford.conf
@@ -6,10 +6,10 @@
 # of a naming policy check and default ACL rules.
 #
 # Written by Russ Allbery <eagle@eyrie.org>
-# Copyright 2007, 2008, 2009, 2010, 2012, 2013
+# Copyright 2007-2010, 2012-2013
 #     The Board of Trustees of the Leland Stanford Junior University
 #
-# See LICENSE for licensing terms.
+# SPDX-License-Identifier: MIT
 
 # default_owner and verify_name come from our policy module.
 use Wallet::Policy::Stanford qw(default_owner verify_name);