clarification on license

git-svn-id: https://hamlib.svn.sourceforge.net/svnroot/hamlib/trunk@264 7ae35d74-ebe9-4afe-98af-79ac388436b8

AUTHORS

@@ -1,7 +1,14 @@
-Authors of the Hamlib API:
+This file is licensed to you under the license specified in the included file
+`COPYING'. Look there for further details.
+
+Authors of the Hamlib API, original code:
 
  Frank Singleton and Stephane Fillod
 
+
+Contributors:
+(if any is missing, please email the current maintainer).
+
 Backends:
 
  icom:		Stephane Fillod