null pointer fix

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@22915 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Added Peter Kortesi's tests + AlternativeBotana added


git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@22916 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e