Added "getData" method to retrieve json-decoded data from JsonResponse

In the context of this issue : https://github.com/laravel/framework/issues/1751
changed response type of 'getData' to mixed
added php's default arguments to getData method of JsonResponse
Merge pull request #1781 from kapv89/patch-5

Added "getData" method to retrieve json-decoded data from JsonResponse
Used getRelation and setRelation in getAttribute

This allows developers more control over eloquent. It doesn't change a thing but allows devs to handle eloquent relations instantiators in a more controlled manner
Merge pull request #2009 from kapv89/patch-6

Used getRelation and setRelation in getAttribute
Fix composer.json
Merge pull request #2012 from Anahkiasen/patch-1

[Fix] Standalone remote component doesn't load its classes
Fix bug.