Fit screen width in landscape orientation
Resize notification view in response to the change of navigation bar bounds
Adjust layout constraints to support rotation
Use self.visible to determine if notification view is on screen
Fix the layout of custom message after rotation
Merge branch 'support-rotation' of https://github.com/bcylin/CSNotificationView into bcylin-support-rotation
Fixed an issue with landscape orientation: The transform transforms `width` to a negative value. refs #28