20160331 - Instant Soft-Reboot to Prior Machine Snapshot

An idea for practical simple memory protection on an otherwised unprotected system. Works similar in concept to emulator instant save and restore but applied to a full system. Reserve 50% of memory for a full machine state snapshot. Deny access to this snapshot memory except during save and restore (ie pages just not in page table). Hook up hotkey combination to save or restore full machine state. On crash, simply restore from snapshot (instant soft-reboot). Design around one full machine barrier per frame for safe snapshot point.