Adds much more descriptive documentation for configuring SC.PickerPanes including the use of new constants SC.POSITION_RIGHT, SC.POSITION_LEFT, SC.POSITION_TOP & SC.POSITION_BOTTOM to make the values of preferMatrix more clear.
Privatizes pointer layout array used internally by SC.PickerPane. Also tidies code a bit.
Sets the windowPadding of SC.PickerPane to default value once rather than checking it each time.
Adds some debug-mode only developer support to prevent the easy mistake of using .append(anchor) with a picker pane instead of .popup(anchor).