Test against PHP7

.travis.yml

@@ -6,6 +6,7 @@ php:
   - 5.5
   - 5.6
   - hhvm
+  - nightly
 
 env:
   - SYMFONY_VERSION=2.6.*
@@ -23,6 +24,7 @@ matrix:
   allow_failures:
     - php: hhvm
     - env: SYMFONY_VERSION=2.7.*@dev
+    - php: nightly
 
 before_script:
   - composer selfupdate