* updates vf-design tokens

* updates design tokens documentation

* re-compiled tokens

* Add link to new documentation location

* Gulp token command tidy

- moves token tasks to a seperate js file
- removes unused dependencies
- adds token generation to dev and build commands
- fixes a couple minor things
- linting
- fix a missing `</main>` tag on theming page
- add vf-content to the index

Co-authored-by: Ken Hawkins <khawkins98@gmail.com>