Add strongly typed attribute updates

[bellebethcooper]

• Create string, float, and int typed attribute update models

• Create protocol for all 3 to conform to

• Expect array of procotol in update func

• Make protocol include func for returning [String: Any] based on model's properties

• Use that func in update func to get dicts to turn into JSON

• Optionally add validation to models to point out errors of mismatched value types, e.g. in string type, check if name matches all known non-string attributes, and throw error if so