Add new puppet versions to travis build matrix

Author: luxflux

.travis.yml

@@ -13,6 +13,10 @@ env:
   - PUPPET_VERSION="~> 3.0.0"
   - PUPPET_VERSION="~> 3.1.0"
   - PUPPET_VERSION="~> 3.2.0"
+  - PUPPET_VERSION="~> 3.3.0"
+  - PUPPET_VERSION="~> 3.4.0"
+  - PUPPET_VERSION="~> 3.5.0"
+  - PUPPET_VERSION="~> 3.6.0"
 matrix:
   exclude:
     - rvm: 1.9.3