change Ctrl-Shift-P to toggle Probability Calculator

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37947 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Ticket #4224: if window.prompt is not available, this solution shall do something like that at least (someone should test it), for ticket #3420 actually

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37948 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e