Travis: Testing against php 7.1

Author: renatomefi

.travis.yml

@@ -12,8 +12,9 @@ matrix:
     - env: COMPOSER_FLAGS="--prefer-lowest"
       php: 5.6
     - php: 7.0
+    - php: 7.1
     - env: COMPOSER_FLAGS="--prefer-lowest"
-      php: 7.0
+      php: 7.1
 
 before_install:
   - composer self-update