Use data-param-language if present

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@26733 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Bugfixes

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@26734 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e