1) Remove the Reset() member in crypto/aes and crypto/des (and
document the change).
2) Turn several empty error structures into vars. Any remaining error
structures are either non-empty, or will probably become so in the
future.
3) Implement SetWriteDeadline for TLS sockets. At the moment, the TLS
status cannot be reused after a Write error, which is probably fine
for most uses.
4) Make crypto/aes and crypto/des return a cipher.Block.
R=rsc, r
CC=golang-dev
https://golang.org/cl/5625045
Consequently, remove many package Makefiles,
and shorten the few that remain.
gomake becomes 'go tool make'.
Turn off test phases of run.bash that do not work,
flagged with $BROKEN. Future CLs will restore these,
but this seemed like a big enough CL already.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5601057
