Enable beaker tests and drop Debian 6 support

.sync.yml

@@ -32,4 +32,7 @@ spec/acceptance/nodesets/ec2/rhel-73-x64.yml
 spec/acceptance/nodesets/debian-70rc1-x64.yml
   delete: true
 .travis.yml:
+  docker_sets:
+    - set: centos6-64
+    - set: debian7-64
   secure: "GkH8b+4jKSQ9TwHnUca5HG5L1g+doS8k1Sp9/K7MBtzFdcWIZxVAc7xUNogq1BbKRm50aNcWbFK7NL5t3GkUH8fNuybZegLEdsrLhJAx57GplC9ip7qVVHsT6GjJ3MrdhbyCOvgHRprMpmENG5vqtXEfrnJ6LSf1MP3DkQPlfrY="

.travis.yml

@@ -23,6 +23,12 @@ matrix:
   - rvm: 2.4.4
     bundler_args: --without system_tests development release
     env: PUPPET_VERSION="~> 5.0" CHECK=build DEPLOY_TO_FORGE=yes
+  - rvm: 2.5.3
+    bundler_args: --without development release
+    env: PUPPET_INSTALL_TYPE=agent BEAKER_IS_PE=no BEAKER_PUPPET_COLLECTION=pc1 BEAKER_debug=true BEAKER_setfile=centos6-64 BEAKER_HYPERVISOR=docker CHECK=beaker
+  - rvm: 2.5.3
+    bundler_args: --without development release
+    env: PUPPET_INSTALL_TYPE=agent BEAKER_IS_PE=no BEAKER_PUPPET_COLLECTION=pc1 BEAKER_debug=true BEAKER_setfile=debian7-64 BEAKER_HYPERVISOR=docker CHECK=beaker
 branches:
   only:
   - master

metadata.json

@@ -31,7 +31,6 @@
     {
       "operatingsystem": "Debian",
       "operatingsystemrelease": [
-        "6",
         "7"
       ]
     },
@@ -51,7 +50,7 @@
   "requirements": [
     {
       "name": "puppet",
-      "version_requirement": ">= 3.8 < 4.0.0"
+      "version_requirement": ">= 3.8 < 5.0.0"
     }
   ]
 }