ContingencyTable: total not reset on update

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30438 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
null pointer fix

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30439 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
larger buttons (from Tool)

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30440 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
smaller sign in dialog

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30441 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
fix warning

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30442 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
add comment

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30443 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e