* 🎉 WindowScroller supports scrollToIndex prop. (@leoasis - bvaughn#643)

* 🎉 Allow ArrowKeyStepper to be used as a controlled component. (@mking-clari - bvaughn#688)
* 🎉New handleScroll method on Grid to better support custom scrollbars. (@5angel - bvaughn#693)
* 🐛 Added edge-case gaurd to WindowScroller  to prevent calling setState when unmounted. (@liorbrauer - bvaughn#689)
* 🐛 Fixed edge-case in Grid where setting an initial scroll-to offset with a height or width of 0 caused the scroll-to prop to be ignored when size later changed. (bvaughn#691)

✨ Better aria roles set for `Table` column cells and headers. (@jchen527

 - bvaughn#681)

🐛 `CellMeasurer` restores `width` and `height` `style` values after measuring to avoid edge-case layout bugs. (@marcelmokos - bvaughn#675)

* ✨ Improved performance for CellMeasurerCache by removing some unnec…

…essary computations for fixed-width/fixed-height use cases. (@RaviDasari - bvaughn#676)

* 🐛 MultiGrid ensures correct row/column indices are passed to CellMeasurerCache for top-right and bottom Grids. (bvaughn#670)

🎉 Add 'nonce' attribute to 'AutoSizer' for better Content Security Po…

…licy compliance (https://www.w3.org/TR/2016/REC-CSP2-20161215/#script-src-the-nonce-attribute). (@akihikodaki - bvaughn#663)

✨ 'Column' renderers now accept a 'columnIndex' parameter as well. This allows multiple 'Table' columns to more easily use 'CellMeasurer' to compute the min row height. (@bamaboy - bvaughn#662)

Clear cell and style cache when controlled-scroll mode Grid stops scr…

…olling. @leoasis - bvaughn#649)

Removed lingering React.PropTypes reference in InfiniteLoader.

Added prop-types dependency to avoid deprecation warnings for React 1…

…5.5+.

Added public animation-friendly API methods to Grid/List/Table for an…

… alternative to props-based animating. (@imadha - bvaughn#641)

Fixed an invalid import in a vendored file

* 🎉 WindowScroller and Grid now support horizontal window-scrolling v…

…ia new autoWidth property. (@maxnowack - PR bvaughn#644)

* 🐛 Fixed a Content Security Policy (CSP) issue in an upstream dependency that impacted users of the Masonry component. For more information see issue bvaughn#640.
* ✨ List and Table always overscan 1 row in the direction _not_ being scrolled to better support keyboard nativigation (via TAB and SHIFT+TAB). For more information see issue bvaughn#625.
* ✨ Grid no longer alters scroll direction for one axis (eg vertical) if a scroll event occurs for another axis (eg horizontal).