message: update imagecarousel readme
diff: @@ -18,6 +18,8 @@ It's placed over everything else in the app using a React Native Modal component
  These two components share context and state. These are managed in `ImageCarouselContext.tsx` and the two components are combined together and provided with context in `ImageCarousel.tsx`
  +Finally, there's the **deep zoom overlay** which is located in `FullScreen/DeepZoom/DeepZoomOverlay.tsx`. This allows the user to see high resolution versions of the image while they pan + zoom in the full screen mode.
  +
  ## How the full screen mode transition works
  When you tap to go fullscreen, this is what happens:
  @@ -37,6 +39,7 @@ It's basically a set of nested scroll views in a modal. Something like this
  <ScrollViewForPinchToZoom>
  <Image />
  </ScrollViewForPinchToZoom>
  + <DeepZoomOverlay />
  </HorizontalFlatListForSwipingBetweenImages>
  </VerticalScrollViewForDismissingFullScreenMode>
  </Modal>
  @@ -45,3 +48,4 @@ It's basically a set of nested scroll views in a modal. Something like this
  - `VerticalScrollViewForDismissingFullScreenMode` provides the vertical-swipe-to-dismiss functionality, and is in `FullScreen/VerticalSwipeToDismiss.tsx`
  - `HorizontalFlatListForSwipingBetweenImages` is given by `FullScreen/ImageCarouselFullScreen.tsx`
  - `ScrollViewForPinchToZoom` is given by `FullScreen/ImageZoomView.tsx`
  +- `DeepZoomOverlay` is given by `FullScreen/DeepZoom/DeepZoomOverlay.tsx`
  