[tests] Use beaker+docker for acceptance tests

Beaker together with docker is a very fast way to do
acceptance testing.
This commit adds basic beaker/docker support:

- Add a debian jessie nodeset
- Test if the module applies idempotentially, so it doesn't
  change resources on a second run with the same parameters.

https://github.com/puppetlabs/beaker/blob/master/docs/Docker-Support.md

1 files changed, 7 insertions, 0 deletions

diff --git a/Gemfile b/Gemfile
index 8925a90..a2756c4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -11,3 +11,10 @@ group :test do
   gem "rspec-puppet-facts"
   gem "mocha"
 end
+
+group :system_tests do
+  gem 'beaker',              :require => false
+  gem 'beaker-rspec',        :require => false
+  gem 'beaker_spec_helper',  :require => false
+  gem 'serverspec',          :require => false
+end