1. Changes travis configuration to use the chrome addon
2. Adds more command line options to runner package
3. Removes grab-headless_shell.sh script
4. Cleans up and adds some environment variables for controlling how
unit tests are ran
5. Fixes a minor issue in chromedp-gen on comment output (for working
with latest protocol definition)
- Refactored API calls to be cleaner
- Changed types that shoudn't be exported to not-exported
- Updated examples with API changes
- Added unit test for Title action
