Allow subclasses to override cache key and background tag for cell background images, since we allow them to override imageForFirst:last:highlighted:drawDivider:. This way the caching facility of imageForFirst:last:highlighted:drawDivider: can be used by subclasses that override that method but call super.
Move NIPageView back into its own file to facilitate its removal and allow clients to avoid pulling in dead code.
Facilitate an easy transition from NIPageView to NIPagingScrollViewPage.
Restore NSString+NimbusCore with calls to NIFoundationMethods
Add debug warnings to get people to remove NSString+NimbusCore
Promote visible pages from the subclassing header to the main header to ease migration.
Restore the pagingScrollView method and add runtime deprecation.