Dependency Audit

Update dependencies using this awesome tool: https://david-dm.org/Workiva/wGulp
I checked each update to ensure there are no breaking changes that will affect us.

Also removed a few dependencies that are no longer in use.

Added the dependency status badge to the README.

## Testing
- Ensure tests pass
- Ensure examples work
- Try it in a wGulp project

@trentgrover-wf 
@evanweible-wf 
@charliekump-wf