Release quality

• Fixed saucelabs safari 12.1 bug
• Run integration tests on IE 11

Developer experience

• Refactor of gulp test into gulp unit|integration|a4a
• WIP: Bot to deploy in-flight PR code for demo / testing (on-demand)
• Refactored / sped up unminified builds by 15%

What's next

• Redeploy owners bot with new reviewers assignment algorithm
• Generate externs for all typedefs found in 3p/ads/bind