The changes were not tested for real in an App Engine environment,
so extra care should be taken. That said, some static testing
was done with pyflakes, and a few existent problems were fixed on
the way.
R=adg
CC=golang-dev
https://golang.org/cl/4378053
Plus automatic package<->project association script.
(This is just a helper script for now. I intend to fully automate
the associations further down the track.)
R=rsc
CC=golang-dev
https://golang.org/cl/1715054
