Data science 20141007 rc

Revisions based on Pull Request: https://github.com/jmmastey/level_up_exercises/pull/150

-clean up errors with main file
-add test_no_winner json data and tests
-convert main.rb into a Results class which takes the calculations from Dataset and wraps in some nice output
-using Hirb gem to format the console output
so far your cohort has been well written to accommodate multiple cohorts, might as well handle the return of the results for them too even if they arent first