added license to composer.json

Author: ctwillie

README.md

@@ -38,7 +38,7 @@ Then add an alias for the class also in `config/app.php` inside the aliases arra
 
 There are two important configurations.
 1. Your USPS user ID:
-    - If you have not received your USPS user ID, follow the link in the [prerequisites (#Prerequisites) section  to register with the 
+    - If you have not received your USPS user ID, follow the link in the [prerequisites](#Prerequisites) section  to register with the 
       United States Postal Service. It is required to use this package.
 2. Whether you want SSL verification enabled for API requests:
     - This setting is set to `true` by default for security reasons. You can override this behavior by setting the `verrifyssl` config     setting to `false`. Do this at your own risk. Or, you can take the steps neccessary to add the certificate to your machine to be     recognized.