CAS - Don't insert error from previous cell

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@36609 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
don't use NEW all the time; styles; show active language in LanguageGUI

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@36610 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e