Chapter 8: Rename current view controller.
Chapter 8: Organise files into groups.
Chapter 8: Extract Twitter API request into separate class/protocol.
Chapter 8: Prove that TwitterAPIRequest works elsewhere.
Revert "Chapter 8: Prove that TwitterAPIRequest works elsewhere."

This reverts commit ba0811e4a72d17e04befcee97b4fa4f86cc163f2.