Numerous Adjustments

- Added isMenuOpened
- Made itemViews a public property (for support of per-item styling)
- Added setPItems: method to support swapping out of Menu Items for different menu types
- Increased menu animation duration to 0.3f and changed to CurveEaseInOut

Signed-off-by: Darren Ehlers <me@darrenehlers.com>
Merge pull request #3 from DoubleNode/master

Numerous Adjustments