Renamed property popUpViewCornerRadius -> cornerRadius

The interface to ASValueTrackingSlider stays the same, it’s just
ASValuePopUpView that changes. When messages are being sent to
ASValuePopUpView it is obvious what the cornerRadius property refers to.
Reset frame after anchorPoint is adjusted
Use rect integral on _textLayer and popUpView frames

Also set popUpView frame before setting arrow offset.
Removed call to positionAndUpdatePopUpView in setup

_showPopUpView method calls positionAndUpdatePopUpView, so it’s not
required in setup.
Cleaned up ';' on methods in implementation files
Improved arrow bezier path drawing
Improved popUpView size calculation