Payment creation expects Pointer instead of LabelMonetaryAccount

[dorxy]

Steps to reproduce:

1. Create a payment using Payment::create or its constructor

What should happen:

1. The counterPartyAlias argument should accept a LabelMonetaryAccount object

What happens:

1. Only a Pointer object is accepted.

It is currently impossible to create a Transferwise payment using the SDK as a Pointer can not hold the information a LabelMonetaryAccount can.