added column totals to github stats table

 also removed commits and authors columns as per byrons request

PR hosted at: 
   http://dashboard.risevision.com:8000

implements  :
    https://trello.com/c/xioy6zX7
    https://trello.com/c/xioy6zX7

also https://github.com/Rise-Vision/Dashboard-proxy/pull/11 needs to be merged at the same time (fixes last 7 days count and removes unused stats)

could @ByronDarlison , @tejohnso @alexey-rise, @alexey-rise review