Add Dockerfile linter

Add dockerfilelint as a developer dependency
Add lint-dockerfile test to package.json

Co-authored-by: Rarity <dongermcdingdong@gmail.com>
Co-authored-by: Abby Frost <afrost3@worcester.edu>
Co-authored-by: Stoney Jackson <dr.stoney@gmail.com>
Co-authored-by: Karl R. Wurst <karl@w-sts.com>

Closes issue #33 (closed)