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git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@23059 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
clean.css renamed for clean-2.css (#2976)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@23060 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e