updated package requirements for symfony 3.0

Author: Nathan Erickson

composer.json

@@ -17,9 +17,9 @@
 
 	"require": {
 		"php": ">=5.3.2", 
-		"symfony/framework-bundle": "~2.7",
-		"symfony/yaml": "~2.7",
-		"symfony/validator": "~2.7",
+		"symfony/framework-bundle": "~2.3 | ~3.0",
+		"symfony/yaml": "~2.3 | ~3.0",
+		"symfony/validator": "~2.3 | ~3.0",
 		"doctrine/common": "~2.4"
 	},