Twitter OAuth client

[snekkalapudi]

Please review "/cc @thecodepath"

[timothy1ee]

Satish, excellent work on this homework, nice job tackling the optionals. Hopefully, things with iOS are starting to come together for you. In the feedback below, I go through a checklist, and if things look good, I'll mention it to let you know you're on the right track, or I'll provide some feedback.

• TwitterClient and models look good. In production, there would be more validation to be robust to unexpected values, but in this homework it was fine to assume a well behaved API. You could move the timestamp code to an extension.
• You should move your assets to Images.xcassets.
• TweetCell looks good, good use of property observers, you can make the view properties private for more encapsulation. Nice job adjusting the Auto Layout constraint constants, although it'd be nice to cut it down to one dynamic constraint if you can.
• Good job with infinite loading.
• Nice job with the custom protocols, note that delegates should be declared as weak to avoid retain cycles.
• In general, Auto Layout constraints look good.