Add copyright to source files

management/mailconfig.py

@@ -1,5 +1,14 @@
 #!/usr/local/lib/mailinabox/env/bin/python
 # -*- indent-tabs-mode: t; tab-width: 4; python-indent-offset: 4; -*-
+#####
+##### This file is part of Mail-in-a-Box-LDAP which is released under the
+##### terms of the GNU Affero General Public License as published by the
+##### Free Software Foundation, either version 3 of the License, or (at
+##### your option) any later version. See file LICENSE or go to
+##### https://github.com/downtownallday/mailinabox-ldap for full license
+##### details.
+#####
+
 
 # NOTE:
 # This script is run both using the system-wide Python 3