* Added UMD (dev and prod) build (@emmanueltouzery - #281)

* Fixed size list and grid components now accurately report 'visibleS…

…topIndex' in 'onItemsRendered'. (Previously this value was incorrectly reported as one index higher.) - (@justingrant - #274)

* Fixed size list and grid components 'scrollToItem' "center" mode when the item being scrolled to is near the viewport edge. - (@justingrant - #274)

* 🐛 Edge case bug-fix for scrollToItem when scrollbars are present (@…

…MarkFalconbridge - #267)

* 🐛 Fixed RTL scroll offsets for non-Chromium Edge (@MarkFalconbridge - #268)
* 🐛 Flow types improved (@TrySound - #260)

* ✨ Deprecated grid props 'overscanColumnsCount' and 'overscanRowsCou…

…nt' props in favor of more consistently named 'overscanColumnCount' and 'overscanRowCount'. (@nihgwu - #229)

* 🐛 Fixed shaky elastic scroll problems present in iOS Safari. #244
* 🐛 Fixed RTL edge case bugs and broken scroll-to-item behavior. #159
* 🐛 Fixed broken synchronized scrolling for RTL lists/grids. #198

* 🐛 Replaced an incorrect empty-string value for 'pointer-events' wit…

…h 'undefined' (@oliviertassinari - PR #210)

🎉 Added new "smart" align option for grid and list scroll-to-item met…

…hods (@gaearon - PR #209)

* 🐛 Add guards to avoid invalid scroll offsets when `scrollTo()` is c…

…alled with a negative offset or when `scrollToItem` is called with invalid indices (negative or too large).