Updates to match current behavior in the iOS 7 Mail app

- Added additional notifications to hide the swipe-to-reveal options under certain conditions, to match the current behavior in the iOS 7 Mail app.
- Documented `TLSwipeForOptionsCell` and `TLOverlayView`.
- Got rid of the annoying `AssertMacros` logs in a recent beta of iOS 7.

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The reason there are so many commits in this pull request is because I removed `project.xcworkspace` and `xcuserdata` from git, as they are unnecessary for proper compiling of the project, and become annoying when committing.