1.18.0

What's new

• Fix Sheet nested scrolling issue (#35, 49ad6f5)
• New onDismiss callback on Dialog and ModalBottomSheet components (67a092d)
• New decayAnimationSpec added on BottomSheet component (49ad6f5)
• BottomSheet's offset now returns the correct amount of the sheet scrolled from the bottom. (61feb93)

Thanks to @commonsguy for minor fixes to Menu docs (#37)