updates travis build matrix

Author: lsmith77

.travis.yml

@@ -19,18 +19,14 @@ env:
 
 matrix:
   include:
-    - php: 5.6
+    - php: 7.0
       env: SYMFONY_VERSION=2.3.*
-    - php: 5.6
+    - php: 7.0
       env: SYMFONY_VERSION=2.8.*
-    - php: 5.6
+    - php: 7.0
       env: SYMFONY_VERSION=3.0.*
     - php: 5.3
       env: SYMFONY_VERSION=2.3.* COMPOSER_FLAGS="--prefer-lowest"
-  allow_failures:
-    - php: 7.0
-    - env: SYMFONY_VERSION=2.8.*
-    - env: SYMFONY_VERSION=3.0.*
   fast_finish: true
 
 before_install: