Re-re-arrange bootasm and bootother.  We can't get bootasm and bootmain on the same page, but this will make them easier to flip between.

Swap bootmain.c and bootother.S.  This puts the whole boot process on one spread, though it separates the two asm files.

replace jstack with asm()s

 * rename c/cp to cpu/proc
 * rename cpu.context to cpu.scheduler
 * fix some comments
 * formatting for printout

pdf has very good page breaks now.
would be a good copy for fall 2009.

PDF at http://am.lcs.mit.edu/~rsc/xv6.pdf

Various changes made while offline.

 + bwrite sector argument is redundant; use b->sector.
 + reformatting of files for nicer PDF page breaks
 + distinguish between locked, unlocked inodes in type signatures
 + change FD_FILE to FD_INODE
 + move userinit (nee proc0init) to proc.c
 + move ROOTDEV to param.h
 + always parenthesize sizeof argument

if no lapic available, use 8253pit for clock
now xv6 runs both on qemu (uniprocessor) and bochs (uniprocessor and MP)

New formatting scripts.

The use/defs extraction in runoff still needs some work
for xv6 code style.