Issue 29 Network State

This pull request addresses issue #29 Provide the Current Network State. 

Just adds two methods into Merlin class which will retrieve the network info from a given context and return the network status. 

~~I was tempted to create a dummy Application in the android manifest and have it static so that you would not be required to pass a context in order to retrieve a network status, but there wouldn't be any guarantee that the onCreate would be called before someone tried to access the isConnected method.~~

^^ Me forgetting that this is a library :tongue: 


what I mean is that this logic is duplicating what the `MerlinService` does. The `isConnected` state is fetched in callbacks.

The issue meant the state within the service, which can be created via the builder with or without  host pinging (if you want a less reliable result)