Update This file method "removeLastObject"

[KevinTao24]

@ColinEberhardt Hey Colin, first thank you very much about this CETableViewBinding Project. I found a issue may be is error. Hope you can check it or right? Kevin.

number of line: 70: the method of "removeLastObject" NSUInteger index = self.count ; all right? not the NSUInteger index = self.count - 1;