TODO: - Add Chi, Pon, Kan, Dora, buttons to TilesViewController - Click on Chi, select three tiles to make chi, colour code - Click Pon/Kan, select one tile to make Pon/Kan, colour code (should the fourth kan tile show up?) - Click on Dora, clear hand tiles, show dora tiles, select up to 10 tiles to make dora, colour code - Click on Dora again, regular hand shows up again (is this a good functionality?) - Remove DoraTilesViewsController