Fixing issue with instanceInitiatedShutdownBehavior when ami root_device_type is instance-store
Replaced shutdown_behavior(string) with terminate_on_shutdown(bool)
Removed unnecessary comments
Modified according to comments by tralamazza
Merge pull request #131 from madhurranjan/madhurranjan_commits

Fixing issue with instanceInitiatedShutdownBehavior when ami root_device...
Update CHANGELOG.md

PR #131
release 0.3.0
dev version