Contributing in README: Use yarn instead of NPM (#2603)
Contributing in README: Use yarn instead of NPM (#2603)

* docs(README): use yarn instead of npm

* docs(README): fix yarn test-watch to use flag

uses flag --watchAll to watch all tests for changes

* docs(README): fix coverage command

* docs(README): use yarn cover for tests and coverage report

* docs(README): remove watch tests instructions

watch tests occurs when you run `yarn test` and press `a` when prompted

* docs(README): re-add Watch tests

* docs(README): fix auto formatting
reactstrap/reactstrap,reactstrap/reactstrap,reactstrap/reactstrap,reactstrap/reactstrap