Fix client.go error handling

This is causing panics in the terraform provider

Author: julienduchesne

client.go

@@ -68,7 +68,8 @@ func (c *Client) request(method, requestPath string, query url.Values, body io.R
 
 	// retry logic
 	for n := 0; n <= c.config.NumRetries; n++ {
-		r, err := c.newRequest(method, requestPath, query, body)
+		var r *http.Request
+		r, err = c.newRequest(method, requestPath, query, body)
 		if err != nil {
 			return err
 		}

client_test.go

@@ -104,6 +104,22 @@ func TestRequest_500(t *testing.T) {
 	}
 }
 
+func TestRequest_badURL(t *testing.T) {
+	server, client := gapiTestTools(t, 200, `{"foo":"bar"}`)
+	baseURL, err := url.Parse("bad-url")
+	if err != nil {
+		t.Fatal(err.Error())
+	}
+	client.baseURL = *baseURL
+	defer server.Close()
+
+	expected := `Get "bad-url/foo": unsupported protocol scheme ""`
+	err = client.request("GET", "/foo", url.Values{}, nil, nil)
+	if err.Error() != expected {
+		t.Errorf("expected error: %v; got: %s", expected, err.Error())
+	}
+}
+
 func TestRequest_200Unmarshal(t *testing.T) {
 	server, client := gapiTestTools(t, 200, `{"foo":"bar"}`)
 	defer server.Close()