Integration tests on Jenkins

[Richard Downer <ri...@apache.org>]

All,

I've set up a job on builds.apache.org to run our integration tests:
https://builds.apache.org/view/A-D/view/Brooklyn/job/incubator-brooklyn-master-integration/

As you may know, our integration tests can be a bit "messy" - they
download software, install it, open network ports, etc. Therefore it's
not polite to run this on the shared build slaves as they could leave
an unclean environment behind them if tests fail.

After discussion with the team running builds.apache.org, they said
that we could run our tests on a cloud-hosted slave and set the option
to ensure that at the end of the test run the cloud instance is shut
down (so there's no unclean environment left behind).

I have set this task to run once a day against the latest artifacts in
the "snapshot" repository.

To start with, it's not running every integration test - it's starting
with a small subset of the Maven modules. As time goes on and we're
more confident that the testing process is working on the
builds.apache.org infrastructure, and that we are getting useful
results out of them and not spamming the dev list, I'll add more
modules to the list until we end up with 100% coverage.

I expect certain cases where our existing integration tests may not be
compatible with the builds.apache.org infrastructure - for example,
some of the tests depend on certain configurations of SSH keys being
available in certain places, and there are probably other assumptions
that will catch us out. These kinds of tests would have to be either
adapted, or moved from the integration test group into a different
category.

Feedback welcome.

Richard.