Added Contact Model (#34)

src/factories/ContactFactory.js

@@ -0,0 +1,16 @@
+'use strict';
+
+const PrivateContact = require('../structures/PrivateContact');
+const BusinessContact = require('../structures/BusinessContact');
+
+class ContactFactory {
+    static create(client, data) {
+        if(data.isBusiness) {
+            return new BusinessContact(client, data);
+        }
+
+        return new PrivateContact(client, data);
+    }
+}
+
+module.exports = ContactFactory;