Relax symfony requirements to reduce Laravel conflicts. Fixed #11

Author: Nathan Macnamara

composer.json

@@ -18,7 +18,7 @@
     "require": {
         "php": ">=5.3.0",
         "illuminate/support": "~5.0",
-        "symfony/yaml": "2.7.*"
+        "symfony/yaml": "~2.0"
     },
     "require-dev": {
         "phpunit/phpunit": "4.*",