Remove direct react dependency, cleanup unused dependencies, upgrade webpack-cli + sass

[acusti]

the direct react and react-dom dependencies cause react and react-dom 16 to be installed when adding react-code-input to a react v17.x application, so i removed the direct react and react-dom dependencies, keeping them only as peer dependencies (fixes #75). storybook still takes care of installing them so that npm start works, and yarn build still works. in addition:

• removed unused dev dependencies: extract-text-webpack-plugin, node-sass (already have sass as a dev dependency), react-addons-test-utils, react-bluekit, webpack-dev-server (fixes Install fails on Node version v12.6.0 #93)
• added prop-types to peer dependencies (there is a direct import from prop-types in ReactCodeInput.js)
• upgraded to latest v3 version of webpack-cli (prepares for the possibility of upgrading storybook, which otherwise leads to Error when trying to build bundle after upgrading to 4.20.0 webpack/webpack#8082)
• upgraded to latest version of sass
• upgraded circle CI’s docker image to the latest node docker image

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.55%. Comparing base (2599c5d) to head (fe4ae2d).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #152   +/-   ##
=======================================
  Coverage   96.55%   96.55%           
=======================================
  Files           2        2           
  Lines         145      145           
  Branches       41       41           
=======================================
  Hits          140      140           
  Misses          5        5           

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[dobesv]

These should still be put into devDependencies to show they are directly used by this package, relying on other packages to install your dependencies isn't as good and when using Yarn PnP won't even work as you must declare explicitly all dependencies you import in your package.

[austinbiggs]

Bump! Is there any chance that this will be merged?