同時定義 class method 和 instance method 的潮潮寫法

You can delegate method to your `class` since your class is also a object in Ruby, fanny~


```ruby
class Foo
  def self.bar
    return "Hello"
  end
  delegate :bar, to: :class
end

```

```ruby

Foo.bar

# => "Hello"

Foo.new.bar

# => "Hello"

```

Awesome.