minor #824 Add testing on PHP 7.1 (stof)

This PR was merged into the 1.4-dev branch.

Discussion
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Add testing on PHP 7.1

Commits
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17830e3 Add testing on PHP 7.1

Author: stof

.travis.yml

@@ -19,12 +19,13 @@ php:
     - 5.5
     - 5.6
     - 7.0
+    - 7.1
     - hhvm
 
 matrix:
     allow_failures:
         - php: hhvm
-        - php: 7.0
+        - php: 7.1
     include:
         - php: 5.3
           env: COMPOSER_FLAGS='--prefer-lowest --prefer-stable' SYMFONY_DEPRECATIONS_HELPER=weak