1. Add prettier and configuration files, but do not format code yet.
2. Configure it for all html|css|js|md code.
3. Fix a bug it found in `CZML Custom Properties.html`
4. Add a pre-commit hook via husky and pretty-quick which will
automatically format changed files when they are staged on the client.
5. Run `prettier-check` during CI and fail the build of code is not
formatted properly.
6. Install eslint config for prettier. This does not enable prettier
checking in eslint (it's unusably slow) but instead just makes sure that
no eslint rules conflict with prettier formatting.
7. Update .editorconfig to match (since prettier respects it)
8. Tweak Sandcastle to handle prettier formated examples