Calling [super updateConstraints] as the final step in updateConstraints implementation

The doc recommends to to this: https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIView_class/index.html#//apple_ref/occ/instm/UIView/updateConstraints

"IMPORTANT
Call [super updateConstraints] as the final step in your implementation."
Merge pull request #8 from madewulf/master

Call [super updateConstraints] as the final step in updateConstraints implementation