Refactor timer system

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@34386 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
More CAS tests in Desktop

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@34387 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
More CAS tests in Desktop

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@34388 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e