Adding testing giac.js


git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@33850 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Support for opening private worksheets

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@33851 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e