[what] 修改關掉HappyCamera的動畫效果: 應該是把main view從上面滑下來 才跟打開HappyCamera的行為一致
[what] fix bug: 關掉camera之後按不到按鈕 滑不了city scroll
[why] 因為只是image-picker (camera)被dismiss掉 但是HappyCameraView還是在的
[how] removeFromSuperview