Save delete tool size in preferences

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@31101 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
polygon triangulation (step 5)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@31103 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e