Added a new UserModel class.

modules/users/user_model.cpp

@@ -0,0 +1,25 @@
+#include "user_model.h"
+
+#include "user.h"
+
+UserModel *UserModel::get_singleton() {
+	return _self;
+}
+
+UserModel::UserModel() :
+		Object() {
+
+	if (_self) {
+		printf("UserModel::UserModel(): Error! self is not null!/n");
+	}
+
+	_self = this;
+}
+
+UserModel::~UserModel() {
+	if (_self == this) {
+		_self = nullptr;
+	}
+}
+
+UserModel *UserModel::_self = nullptr;

modules/users/user_model.h

@@ -0,0 +1,21 @@
+#ifndef USER_MODEL_H
+#define USER_MODEL_H
+
+#include "core/object.h"
+
+#include <string>
+
+class User;
+
+class UserModel : public Object {
+public:
+	static UserModel *get_singleton();
+
+	UserModel();
+	~UserModel();
+
+protected:
+	static UserModel *_self;
+};
+
+#endif