Fix typo in objective_functions.rst

Change "relitave gain" to "relative gain."
Merge pull request #330 from TimDumol/patch-1

Fix typo in objective_functions.rst
Use public Travis build
Merge pull request #333 from Yelp/sclark_331_fix_travis

Use public Travis build
Fix travis typo

Use public travis endpoint
Fix travis typo

Use public docker image as well as link...
Merge branch 'master' of https://github.com/Yelp/MOE into norases_255_create_epsilon_greedy_bandits