Removing master branch in favor for a gh-pages branch.

This pull request will create a Github pages page for your GDI UX Basics class. Some things to take into account:

- `master` branch no longer exists, as it is easier to just maintain one branch.
- Once this is merged in, you'll be able to see your slides at the following location: snkahn.github.io/gdi-ux-basics/slides/class-[number].html