remove PHP 5.3.3 from travis test matrix

Author: lsmith77

.travis.yml

@@ -18,7 +18,7 @@ env:
 
 matrix:
   include:
-    - php: 5.3.3
+    - php: 5.3
       env: SYMFONY_VERSION=2.3.* COMPOSER_FLAGS="--prefer-lowest"
     - php: 5.6
       env: SYMFONY_VERSION=2.3.*