Fix the button error for GBInfiniteViewControllersDemo
Fix the tableView inset bug.
Fix the enumerateObjectsUsingBlock bug from iOS6
Fix the tableView insets bug from iOS6.

but the iOS6 view frame is error, origin y is 20.
This demo can not see refresh view on screen.
Merge pull request #19 from xhzengAIB/master

Fix the button error for GBInfiniteViewControllersDemo