Fix build matrix

Author: stephenrjohnson

.travis.yml

@@ -2,11 +2,18 @@ language: ruby
 bundler_args: --without system_tests
 rvm:
   - 2.3.1
+  - 1.9.3
 script: "bundle exec rake test"
 env:
   matrix:
-    - PUPPET_GEM_VERSION="< 4.0.0"
-    - PUPPET_GEM_VERSION="< 4.0.0" FUTURE_PARSER="yes" STRICT_VARIABLES="no"
-    - PUPPET_GEM_VERSION="< 4.0.0" FUTURE_PARSER="yes" STRICT_VARIABLES="yes"
-    - PUPPET_GEM_VERSION="> 4.0.0"
-    - PUPPET_GEM_VERSION="> 4.0.0" STRICT_VARIABLES="yes"
+    include:
+      - rvm: 2.3.1
+        env: PUPPET_GEM_VERSION="< 4.0.0"
+      - rvm: 2.3.1
+        env: PUPPET_GEM_VERSION="< 4.0.0" FUTURE_PARSER="yes" STRICT_VARIABLES="no"
+      - rvm: 2.3.1
+        env: PUPPET_GEM_VERSION="< 4.0.0" FUTURE_PARSER="yes" STRICT_VARIABLES="yes"
+      - rvm: 1.9.3
+        env: PUPPET_GEM_VERSION="> 4.0.0
+      - rvm: 1.9.3
+        env: PUPPET_GEM_VERSION="> 4.0.0" STRICT_VARIABLES="yes"