65. NG 事項
・キーボード使用
・スクロールビューの配置
・大きすぎるコンテンツ(高さ)
https://developer.apple.com/library/ios/documentation/General/Conceptual/ExtensibilityPG/NotificationCenter.html
66. 参考文献
App Extension Programming Guide
https://developer.apple.com/library/ios/documentation/General/Conceptual/ExtensibilityPG/index.html
WWDC2014 資料
https://developer.apple.com/videos/wwdc/2014/
Creating Extensions for iOS and OS X, Part 1
Creating Extensions for iOS and OS X, Part 2