Changing javagiac.dll's to the latest version in desktop/kickstart.xml

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@33267 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
GetPNGBase64 method to API

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@33268 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Adding getVisible() method that worked with 4.2 but disappeared in 4.4.

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@33269 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
update CAS tests

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@33270 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e