Add Travis-CI support

This patch adds a suitable .travis.yml for supporting travis based testing,
and includes a Gemfile with the required ruby dependencies.

Signed-off-by: Ken Barber <ken@bob.sh>
Remove puppet from Gemfile

Signed-off-by: Ken Barber <ken@bob.sh>
Merge pull request #493 from kbarber/ticket/master/travis-ci

travis-ci integration