--use-leap-wheels sets --trusted-host (remove it when we have a proper
  cert) and WHEELHOUSE to https://ftp.lizard.leap.se

Until we get ftp.lizard cname, use lizard as the wheels server.

In case the http client loses connection, it has to clear
it's timeout or the reactor will be left in a dirty state
Fixing this solves a problem with some of the tests in Soledad
that were trying to run on a dirty reactor

generate_wheels uses $WHEELHOUSE to generate and store the wheels for
requirements.pip and requirements-testing.pip (if it exists).

pip_install_requirements.sh installs requirements.pip from them if
possible (if not, then it fetches them from pypi) or, if passed the
--testing flag, it installs requirements-testing.pip.

we stopped using protobuf after the events submodule refactor

Since register and unregister cant be used without full zmq initialization,
it should make sense to also check flag for them.