Eliminate annoying Pseudodesc structure.
Eliminate unnecessary parts of mmu.h.

Add user.h for prototypes.
Add cons_puts for cleaner output.

Rename fd_reference to more suggestive fd_incref.
(Fd_reference sounds like it might just return the ref count.)

Attempt to clean up newproc somewhat.

Also remove all calls to memcpy in favor of
memmove, which has defined semantics when
the ranges overlap.  The fact that memcpy was
working in console.c to scroll the screen is not
guaranteed by all implementations.

New scheduler.

Removed cli and sti stack in favor of tracking
number of locks held on each CPU and explicit
conditionals in spinlock.c.

Undo change from this morning that wasn't intended to get in.

Change fetchint, fetcharg, and putint to return -1 on error, 0 on success.
They had been returning 0 on error, 1 on success, but all the callers
were checking for return value < 0.

wakeup1() assumes you hold proc_table_lock
sleep(chan, lock) provides atomic sleep-and-release to wait for condition
ugly code in swtch/scheduler to implement new sleep
fix lots of bugs in pipes, wait, and exit
fix bugs if timer interrupt goes off in schedule()
console locks per line, not per byte