Expose scroll seek in grouped virtuoso

Merged the PR #110

Add Scarf for analytics

I have no idea how many people use this library, so I hope Scarf will help me with that.

Various Bug Fixes

• Switched to useEffect, as per the warning from #106 (likely, it had SSR broken as well)
• Fixed regression of GroupContainer and ItemContainer broken in 0.16 (#105)
• Fixed errors in snapshot tests (#100)

Fix rendering inconsistencies when changing total count

#99 is included here.

New data-key property, set to a new value redraw list if data has changed (but the total count is the same). #90

Scrolling of very large lists is now possible

The list can now support millions of items, working around the browser maximum element height limitation.

Fixed #54 , #69, #87, #86

bottomStateChange exposed in GroupedVirtuoso

Merged #84

Bug fix for attaching / detaching grouped virtuoso

Fixes the issue caught in #83

CSP Compliance, bring `rangeChanged` to GroupedVirtuoso

Two PRs merged:

• A change which makes the component CSP compliant (#77)
• Port of rangeChanged to the GroupedVirtuoso component variant. (#81)

Fix scrollToIndex regression

The issue was spotted in #75 and was related to changes aimed at making scrollToIndex more resilient.

Fix warnings in React 16.13.0

Virtuoso and GroupedVirtuoso are now functional components. This should not cause any change in the behavior, but if it does - please open an issue!