cool down improvements

- even if a task is always failing, don’t go into cool down unless it’s
failing rapidly.
Merge branch 'master' into hs_staging
Merge branch 'master' into hs_staging
fixing style issues
ignore build.json file
Merge pull request #227 from HubSpot/hs_staging

Cooldown improvements
Merge pull request #8 from HubSpot/master

Merge from hubspot