role::ci::slave::labs

A specific Jenkins CI slave that run on slave. Comes with some packages
which are not suitable for production as defined in the new class
contint::packages::labs (installs npm/python-pip for now).

Possible issue to look at is how puppet handle sub directories. I used
the layout:

Change-Id: Ie294906834cdb86ac07b9d9b791153a1c61e05f7
contint::packages        modules/contint/manifests/package.pp
contint::packages::labs  modules/contint/manifests/package/labs.pp