[giac] partial fix for sum

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@25254 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Normal instead of italic for FormulaText

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@25255 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Changing giac.js to the latest version in web/kickstart.xml

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@25256 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Fix for font size heuristic, code cleanup

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@25257 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e