Implement presentation handlers

[aldy505]

This should be easy. For each handler, all you need to do is:

1. Parse the request body (if any), to a schema that is already defined on the presentation/schema package.
2. Convert the request schema into common business model
3. Execute the business function
4. Convert the returned business model into the response schema
5. Send it

mock-shipping-provider/presentation/estimate.go

Lines 5 to 7 in 413bb3e

	func (d *Dependency) EstimateHandler(w http.ResponseWriter, r *http.Request) {
	// TODO!
	}

mock-shipping-provider/presentation/order.go

Lines 5 to 7 in 413bb3e

	func (d *Dependency) OrderHandler(w http.ResponseWriter, r *http.Request) {
	// TODO!
	}

mock-shipping-provider/presentation/status_history.go

Lines 5 to 7 in 413bb3e

	func (d *Dependency) StatusHistoryHandler(w http.ResponseWriter, r *http.Request) {
	// TODO
	}