Merge pull request #8 from trello/exercise-two

exercise-two: pinging and ponging
updated pods
make layout work if you open in landscape
diff handling works if someone disconnects and reconnects with the same email
animation 🚀
Merge remote-tracking branch 'github/exercise-one' into HEAD
fixed podfile
Merge branch 'client-improvements' into HEAD

Conflicts:
	client/Pods/Pods.xcodeproj/project.pbxproj
drag-and-drop: renders right, but doesn't send updates
after a drop, don't jump back to previous socket-known position
An elusive king appears!
Shh, ghc-mod, it'll be OK
read, modify shorthand
Move seconds into one place
Scoring!
Merge remote-tracking branch 'github/hao' into drag-and-drop
added STNWebSocket, built on top of FCTWebSocket
pedantic comment correction
nicer drag handling: signal of signals, instead of weird hybrid signal + state observation
ChessBoardVC takes an STNWebSocket instead of a single signal