Add support for testing via wwtd

`wwtd` is a useful utility for running tests like they would be run
within Travis CI.

Change-Id: I5786c4267d322e73b9489a8be6d91faebc690c91
Reviewed-on: http://gerrit.causes.com/45027
Tested-by: jenkins <jenkins@brigade.com>
Reviewed-by: Shane da Silva <shane.dasilva@brigade.com>