Hooks rewrite and increased test coverage

[jakeboone02]

This PR rewrites react-querybuilder to use React Hooks. It also increases test coverage to 100% and avoids warnings in React 16.9 about unsafe lifecycle methods.

This library will not be compatible with React 17 without changing the lifecycle names to "UNSAFE_*", so some change is necessary anyway. Might as well future-proof it with Hooks.

[codecov-io]

Codecov Report

Merging #87 into master will increase coverage by 21.15%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master    #87       +/-   ##
=========================================
+ Coverage   78.84%   100%   +21.15%     
=========================================
  Files           7     11        +4     
  Lines         156    169       +13     
  Branches       24      9       -15     
=========================================
+ Hits          123    169       +46     
+ Misses         32      0       -32     
+ Partials        1      0        -1

Impacted Files	Coverage Δ
src/Rule.jsx	100% <100%> (ø)	⬆️
src/utils/getLevel.js	100% <100%> (ø)
src/QueryBuilder.jsx	100% <100%> (+37.5%)	⬆️
src/utils/findRule.js	100% <100%> (ø)
src/utils/generateValidQuery.js	100% <100%> (ø)
src/RuleGroup.jsx	100% <100%> (ø)	⬆️
src/utils/isRuleGroup.js	100% <100%> (ø)
... and 1 more

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[pavanpodila]

Looks great!

[jakeboone02]

Thanks, @pavanpodila! I went ahead and merged this into master. Can you publish a new version on npm? It may need a major version bump since it now requires React >= 16.8.

[pavanpodila]

Done: https://www.npmjs.com/package/react-querybuilder. Thanks for the great work Jake! 🚀