Added sticky Grid to FAQ

Author: Brian Vaughn

README.md

@@ -81,7 +81,9 @@ Here's a [Code Sandbox demo](https://codesandbox.io/s/2w8wmlm89p).
 
 ### Does this library support "sticky" items?
 
-Yes, although it requires a small amount of user code. Here's a [Code Sandbox demo](https://codesandbox.io/s/0mk3qwpl4l).
+Yes, although it requires a small amount of user code. Here are Code Sandbox demos for list and grids:
+* [List demo](https://codesandbox.io/s/0mk3qwpl4l)
+* [Grid demo](https://codesandbox.io/s/vqk32863wy)
 
 ## License