Use a pack -> install technique to recreate local packages

[tmeasday]

As suggested by npm/npm#15900. This is a workaround until we get a better resolution of #1286

Issue: #1331

What I did

Added a build-packs command that builds a pack (this is what npm does right before publishing) for each of our packages, and moves them to packs/$name.tgz (note, no version number).

test-cra depends on those packs directly, which recreates the old npm<5 local package install.

How to test

npm install
npm run bootstrap
# you may need to clear out node_modules first
npm run bootstrap:test-cra
npm run bootstrap:react-native-vanilla

# this should pass! (+ in CI)
npm test

# also, test that the app works
cd examples/test-cra
npm start
npm run storybook

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (1266-fix-components-deps@e5041fa). Click here to learn what that means.
The diff coverage is n/a.

@@                     Coverage Diff                     @@
##             1266-fix-components-deps    #1332   +/-   ##
===========================================================
  Coverage                            ?   13.75%           
===========================================================
  Files                               ?      202           
  Lines                               ?     4623           
  Branches                            ?      522           
===========================================================
  Hits                                ?      636           
  Misses                              ?     3516           
  Partials                            ?      471

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[storybookbot]

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[shilman]

awesome sauce! this is a little weird, but then again so is npm 😝