More license stuff...

COPYING

@@ -0,0 +1,20 @@
+compton - a compositor for X11
+
+Based on xcompmgr, originally written by Keith Packard, with modifications
+from several contributors (according to the xcompmgr man page): Matthew Allum,
+Eric Anholt, Dan Doel, Thomas Luebking, Matthew Hawn, Ely Levy, Phil Blundell,
+and Carl Worth. Menu transparency was implemented by Dana Jansens.
+
+Numerous contributions to compton from Richard Grenville.
+
+See the CONTRIBUTORS file for a complete list of contributors
+
+This source code is provided under:
+
+	SPDX-License-Identifier: MPL-2.0 AND MIT
+
+And the preferred license for new source files in this project is:
+
+	SPDX-License-Identifier: MPL-2.0
+
+You can find the text of the licenses in the LICENSES directory.