Extend the Connection class to "PUT" a file

[BillFarber]

The Connection class permits the user to perform a PUT request, possibly including data. However, I have found that this method is not convenient for uploading files. Particularly non-json files.

Therefore, I will be implementing a putFile method in the Connection class. This method will accept a data argument instead of a payload argument. Additionally, when it calls Request.put, it uses the data argument instead of the json argument.