MallarDuck => MallardDuck

[chasezimmy]

Just a small misspelling I noticed when reading through the notes:

public class MallarDuck extends Duck{
    public MallarDuck(){
        flyBehavior = new FlyWithWings();
        quackBehavior = new Quack();
    }
}

Should read:

public class MallardDuck extends Duck{
    public MallardDuck(){
        flyBehavior = new FlyWithWings();
        quackBehavior = new Quack();
    }
}

设计模式.md

[CyC2018]

@chasezimmy thx~