Clarifying license in README and metadata

README.md

@@ -12,7 +12,7 @@
 
 # About Kdenlive
 
-[Kdenlive](https://kdenlive.org) is a Free and Open Source video editing application, based on MLT Framework and KDE Frameworks 5. It is distributed under the [GNU General Public License Version 2](https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html).
+[Kdenlive](https://kdenlive.org) is a Free and Open Source video editing application, based on MLT Framework and KDE Frameworks 5. It is distributed under the [GNU General Public License Version 3](https://www.gnu.org/licenses/gpl-3.0.en.html) or any later version that is accepted by the KDE project.
 
 # Building from source
 

data/org.kde.kdenlive.appdata.xml

@@ -2,7 +2,7 @@
 <component type="desktop">
   <id>org.kde.kdenlive.desktop</id>
   <metadata_license>CC0-1.0</metadata_license>
-  <project_license>GPL-2.0+</project_license>
+  <project_license>LicenseRef-KDE-Accepted-GPL</project_license>
   <name>Kdenlive</name>
   <name xml:lang="ar">كدينلايڤ</name>
   <name xml:lang="az">Kdenlive</name>