Update Travis test suite

.travis.yml

@@ -2,38 +2,12 @@
 sudo: false
 language: ruby
 rvm:
-  - 2.0.0
   - 2.1.10
-  - 2.2.5
-  - 2.3.1
+  - 2.2.8
+  - 2.3.5
 env:
-  - PUPPET_GEM_VERSION="~> 3.4.0"
-  - PUPPET_GEM_VERSION="~> 3.5.0"
-  - PUPPET_GEM_VERSION="~> 3.6.0"
-  - PUPPET_GEM_VERSION="~> 3.7.0"
-  - PUPPET_GEM_VERSION="~> 3.8.0"
-  - PUPPET_GEM_VERSION="~> 4.4.0"
-  - PUPPET_GEM_VERSION="~> 4.6.0"
+  - PUPPET_GEM_VERSION="~> 4.7.0"
+  - PUPPET_GEM_VERSION="~> 4.9.0"
+  - PUPPET_GEM_VERSION="~> 4.10.0"
 matrix:
-  exclude:
-    - rvm: 2.2.5
-      env: PUPPET_GEM_VERSION="~> 3.4.0"
-    - rvm: 2.3.1
-      env: PUPPET_GEM_VERSION="~> 3.4.0"
-    - rvm: 2.2.5
-      env: PUPPET_GEM_VERSION="~> 3.5.0"
-    - rvm: 2.3.1
-      env: PUPPET_GEM_VERSION="~> 3.5.0"
-    - rvm: 2.2.5
-      env: PUPPET_GEM_VERSION="~> 3.6.0"
-    - rvm: 2.3.1
-      env: PUPPET_GEM_VERSION="~> 3.6.0"
-    - rvm: 2.2.5
-      env: PUPPET_GEM_VERSION="~> 3.7.0"
-    - rvm: 2.3.1
-      env: PUPPET_GEM_VERSION="~> 3.7.0"
-    - rvm: 2.2.5
-      env: PUPPET_GEM_VERSION="~> 3.8.0"
-    - rvm: 2.3.1
-      env: PUPPET_GEM_VERSION="~> 3.8.0"
   fast_finish: true

Gemfile

@@ -8,17 +8,3 @@ end
 
 gem 'puppetlabs_spec_helper', :require => false
 gem 'metadata-json-lint',     :require => false
-
-## compatibility
-
-platforms :ruby_18 do
-  # https://github.com/rspec/rspec-core/issues/1864
-  gem 'rspec', '< 3.2.0',  :require => false
-  gem 'rake',  '< 11.0.0', :require => false
-end
-
-platforms :ruby_18, :ruby_19 do
-  gem 'json',           '< 2.0.0',  :require => false
-  gem 'json_pure',      '< 2.0.0',  :require => false
-  gem 'parallel_tests', '< 2.10.0', :require => false
-end