Minor changes in README. Added fault debugging printfs that can be turned on/off.

Tasks boot fine up to doing ipc using their utcbs.

UTCB PLAN:

- Push ipc registers into private environment instead of a shared utcb,
  but map-in a shared utcb to pass on long data to server tasks.
- Shared utcb has unique virtual address for every thread.
- Forked child does inherit parent's utcb, but cannot use it to communicate to
  any server. It must explicitly obtain its own utcb for that.
- Clone could have a flag to explicitly not inherit parent utcb, which is the
  right thing to do.
- MM0 serves a syscall to obtain self utcb.
- By this method, upon forks tasks don't need to map-in a utcb unless they want
  to pass long data.

tasks/mm0/include/vm_area.h

@@ -14,6 +14,13 @@
 #include <arch/mm.h>
 #include <lib/spinlock.h>
 
+// #define DEBUG_FAULT_HANDLING
+#ifdef DEBUG_FAULT_HANDLING
+#define dprintf(...)	printf(__VA_ARGS__)
+#else
+#define dprintf(...)
+#endif
+
 /* Protection flags */
 #define VM_NONE				(1 << 0)
 #define VM_READ				(1 << 1)