Created CRA kitchen sink addons example

[shilman]

Issue: #1220

What I did

The work with RN apps got too complicated, so I just started over:

• renamed example to cra-kitchen-sink
• added simple info, notes, centered, knobs examples
• minor cleanup

How to test

npm install && npm run bootstrap
cd examples/cra-kitchen-sink
npm run storybook

[codecov]

Codecov Report

Merging #1288 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           master    #1288    +/-   ##
========================================
  Coverage   13.71%   13.71%            
========================================
  Files         207      207            
  Lines        4646     4646            
  Branches      529      637   +108     
========================================
  Hits          637      637            
+ Misses       3543     3464    -79     
- Partials      466      545    +79

Impacted Files	Coverage Δ
app/react/src/server/babel_config.js	44.82% <0%> (ø)	⬆️
app/react/src/server/iframe.html.js	0% <0%> (ø)	⬆️
app/react-native/src/preview/story_kind.js	0% <0%> (ø)	⬆️
addons/knobs/src/components/types/Boolean.js	11.62% <0%> (ø)	⬆️
lib/ui/src/modules/shortcuts/actions/shortcuts.js	6.25% <0%> (ø)	⬆️
lib/ui/src/modules/ui/configs/handle_keyevents.js	33.33% <0%> (ø)	⬆️
...codemod/src/transforms/update-organisation-name.js	40.62% <0%> (ø)	⬆️
addons/knobs/src/components/PropField.js	10.86% <0%> (ø)	⬆️
lib/ui/src/modules/api/actions/api.js	49.42% <0%> (ø)	⬆️
addons/info/src/components/PropTable.js	0% <0%> (ø)	⬆️
... and 20 more

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[tmeasday]

🎉

[ndelangen]

🎈