Enhancement: Specify matrix inclusions

Author: localheinz

.travis.yml

@@ -1,16 +1,15 @@
 language: php
 
-php:
-  - 5.3.3
-  - 5.3
-  - 5.4
-  - 5.5
-  - 5.6
-  - 7
-  - hhvm
-
 matrix:
   fast_finish: true
+  include:
+    - php: 5.3.3
+    - php: 5.3
+    - php: 5.4
+    - php: 5.5
+    - php: 5.6
+    - php: 7
+    - php: hhvm
   allow_failures:
     - php: 7