Updated changelog

Documentation/DeveloperHelpSources/changelog.docu

@@ -9,6 +9,8 @@
          - Queued cross plugin interconnection feature
          - Use QOpenGLWidget
          - Switched to Qt command line parsing and removed SimpleOpt
+         - Fix clang warning by avoiding GNU extension
+         - Do not automatically save file immediately after loading with ctrl-o
      - <b>ACG</b>
          - Clamp shininess in Materialnode (caused GL Errors)
          - Better Material support in Materialnode (emissive and refractive materials)