Fixed the pod spec; Added a demo project written in Swift

Hi Jesse

I added JCTiledScrollView to my podspec file but Cocoapods said it could not find the repository. Then I tried to 'pod lib lint', it said the podspec had errors. So I forked it and corrected the errors. I pushed the podspec, but it's currently downloading from my fork
https://github.com/yichizhang/JCTiledScrollView.git

If you accept the pull request and create a release (0.0.2), I can update the podspec and make it point to 
https://github.com/jessedc/JCTiledScrollView.git

Or you can do it by yourself by running `pod lib lint` first; then `pod trunk push`.

I also added `import <UIKit/UIKit.h>` for a file, without which it wouldn't compile in Swift.

I also added a new demo project written in Swift; I think that would help some people.