add Kernel.checkInteger() to Div/Mod

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@33063 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
fix test

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@33064 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
SetCaption[] also changes label mode

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@33065 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e