This seems to be more trouble than its worth, and much of
the remaining build time (except the push itself). We can
cache the cross-build/golang images between builds - it's
not going to kill us, and it'll save the occasional weird
flake of not finding an image when it tries to rm one of
these.
This will increase build times on Jenkins, but should make the build
times consistent and make them pull from sources every time versus
leftover artifacts. Also upping timeout. (Try to address recent
some aborted builds.)
And a config description. This doesn't yet have much - first want to
make sure I can do the build job. Next I'll submit the e2e script with
its twiddles and switch those over. (After going to 3 e2es, I think
it's finally time for version control.)
Joe Finney