TravisCI and AppVeyor run the tests in very slow VMs.
Some of our tests can't cope with that. Running less tests
in parallel should make them somewhat less flakey.
(cherry picked from commit b0a6b979a3f12e91cfbc89850bfaa00c46653e85)
The new build script, ci.go, replaces some of the older shell scripts.
ci.go can compile go-ethereum, run the tests, create release archives
and debian source packages.
(cherry picked from commit 6c33ba14a4db99409657e6a68a7c629e09ceee3f)