Make GetResponse in query package return a defined interface

[p0mvn]

More information about this issue can be found in the following PR comment

A/C

• new interface is defined wrapping map[string]interface{}
• GetAsString and GetAsFloat implemented

[dhiaayachi]

After some thoughts I think the best way would be to make the user pass a response object that we would populate.

currently the user need to do something like this:

        newton := newton.New("", "")
	q := &query.OpenOrders{}
	response, _ := newton.Do(q)
	resp := response.Body.(*query.OpenOrdersResponse)
	fmt.Println((*resp)[0].Price)

Which I think is not ideal, a better way to do this would be:

        newton := newton.New("", "")
	q := &query.OpenOrders{}
        r := query.OpenOrdersResponse{}
	responseCode, _ := newton.Do(q,&r)
	fmt.Println(r[0].Price)

What you think about this @akhtariev ?

[p0mvn]

That looks good to me. Maybe we could even make it as part of a response package? So it would be:

r := response.OpenOrders{}

[dhiaayachi]

Yes great idea, I will work on this when I have some spare time.