figured out how to use baseurl

Only used for project sites (gh-pages branch), not user sites (master
branch). Set baseurl as the <project name> of the repo, then pass an
empty string to the `—baseurl` flag (`—baseurl ‘’`>. Be sure to start
<project name> w/ forward slash and end w/out a trailing slash. See the
docs for more, http://jekyllrb.com/docs/github-pages/.