add jekyll tasks to the gruntfile using the shell

I tried using grunt-jekyll in another branch but it did not support
passing options in and nothing worked.
integrate bgShell into grunt workflow
delete the Makefile now that we're all grunt all the time
Merge remote-tracking branch 'origin/gh-pages' into all-grunt-all-time
add livereload to html files too
Merge pull request #12 from texastribune/all-grunt-all-time

Move jekyll functionality from makefile to grunt