Added new push optional parameters and the possibility to send a json payload instead of a simple string message
keyword parameter type renamed to device_type. type is a reserved keyword
Merge pull request #1 from mgalves/master

Thanks for the work. I will break down the "send text" and "send json" into two distinct methods (Push.message and Push.alert?)
breaking down of Push send into two distinct methods, Push.alert (for json data) and Push.message (for text). Uses 'where' as an optional variable to make specific queries, and pass any other optional parameters through **kw)