Added More Examples

- Added IB examples to show off prototype cells / headers / footers
- Added actions to show off insert / move / delete / add
Clean up

Updated old code examples to match the new IB examples.   Changed toggleSectionData to update the title of the bar item.  Instead of adding 50 items, only add 5
Fixed typo

- In the insertItems we should be inserting the newItems, instead of inserting the current items.
Minor tweaks

- If we pass nil for the viewClass in the supplementary view registration, then we shouldn't freak out.
- Passing nil to `pathForResource:` will freak out.
Merge pull request #3 from urbn/examples

Examples