- Add new methods to set gestures. The new allows you to set a block completion handler for more
flexibility.

- Using `UIImage` instead of image name.
- Tweaked a little bit the demo project.
Improved transition between states.
Deleted the old methods using image names and custom initializers.
Deleted non necessary delegate method.
Added iOS7 spring animation.
Fixed issue with color indicator view in new spring animation.
Changed view manipulation mechanism.

Instead of manipulating the content we now take a snapshot of the cell
view and animate this one.
This allows us the use of accessory views and avoid strange UI glitches.
Add support for UIView instead of UIImage.
Various code cleanup.
Improved code documentation.
Fixed some typos.
Updated README with API modification newly introduced.
Updated Copyright & License.
Updated podspec tag version to 2.0.0.
Various little adjustments in demo project .
Calling the `swipeTableViewCellDidEndSwiping` delegate method when swiping just ended.
Merge pull request #53 from alikaragoz/dev

Merge of changes made in dev branch.