Unhandled page fault should trigger debugger

[EdNutting]

An unhandled page fault (which is every page fault at the moment) should set Debug_Suspend on all threads of the faulting process, switch process and then continue cleanly (rather than outputting a bunch of data and crashing the system, as currently happens). Outputting the data over COM1 (BasicConsole) would still be useful!

This probably depends on issue #91