ModifiableMetadata changes for revisions 20873:20874

Changes in GeoTools header only. The removal of the "or (at your option) any later version" clause must be keep in Geotk for every classes having contribution from a developer other than those who accepted re-licensing. This header does not apply to Apache SIS, since the above-cited contributions are omitted.

Command line:

svn diff --extensions "--unified --ignore-space-change --ignore-all-space --ignore-eol-style" -r20873:20874 https://svn.osgeo.org/geotools/trunk/modules/library/metadata/src/main/java/org/geotools/metadata/ModifiableMetadata.java
Revision 20873Revision 20874
/*
 *    Geotools2 - OpenSource mapping toolkit
 *    http://geotools.org
 *    (C) 2002, Geotools Project Managment Committee (PMC)
 *
 *    This library is free software; you can redistribute it and/or
 *    modify it under the terms of the GNU Lesser General Public
 
/*
 *    GeoTools - OpenSource mapping toolkit
 *    http://geotools.org
 *    (C) 2004-2006, GeoTools Project Managment Committee (PMC)
 *
 *    This library is free software; you can redistribute it and/or
 *    modify it under the terms of the GNU Lesser General Public