Standardize/enforce code formatting on the project

Prescribed Solution:

• Format all of the extension code
  • Python (using black)
  • js, jsx, ts, tsx, json, css, less, sass (using prettier)
• ~Format on commit~
• Format on save (user settings, opt in using)
  • Use prettier extension
  • Use python extension with black
• Recommend prettier extension in .vscode/extensions.json
  • Use prettier extension
  • Use python extension with black
• Prettier Config settings
  • Prettier rc config (editor agnostic, also picked by CI)
  • ~.vscode/settings~
• CI check for all pipelines (black & prettier)
  • PR pipeline
  • CI Pipeline
• Update contributing guide
• Configure prettier to use tslint (ensure this works on CI)
  • TIP - Look for prettier plugins (plenty good ones)

~Set up [pre-commit](https://pre-commit.com/) and some [hooks](https://pre-commit.com/hooks.html) for anything which runs quickly:~

• ~Prettier~
• ~Black ~
• ~tslint~
• ~pre-commit~

~… etc.~

[brettcannon]

@DonJayamanne why do you not want to install Python to work on the Python extension for VS Code? Inquiring minds want to know! 😉

And I think we can skip doing pre-commit hooks because we have something called extensions. 😁 Pre-commit hooks are great as a standardized way to help make sure people meet some requirement before sending code to CI. But since we have standardized our tooling all the way up to the editor, we can actually just standardize on VS Code extensions to do the formatting for us and then let CI enforce that requirement as @d3r3kk suggested.

[d3r3kk]

As an alternate view: Why don’t we simply use a faster check at the onset of the CI build to handle these pre-commit issues, and give contributors all the information they need to reproduce the CI build ‘quick checks’ on their own machine should the need arise?

Note: I personally have never been a huge fan of pre-commit checks.

Until I found the npm run -s precommit command so I could run it at my will, I found my enjoyment of checking in somewhat… reduced. I like it when the build machine tells me (quickly, preferably) when I’ve messed up simple stuff like linting/etc… and then gives me the tools to just check it on my own.