amazon-ecs-cli-v2: Release v0.0.7

🎉 Features and bug fixes

• #644: Enable custom AWS resources by writing AWS CloudFormation templates under the "addons/" directory. See the wiki for more details.
• #597: Override the default health check path "/" by modifying thehealthcheck field in the application manifest.
• #733: app show now displays the protocol of the application's URL.
• #729: Add ecs-preview deploy command that's an alias of ecs-preview app deploy.

🚨 Backwards incompatible changes

• #748: The first application that you create with ecs-preview init will now listen to the default path "/" and all subsequent applications will listen to "/{appName}"
• #726: Support service discovery.

🙏 Contributions

• #728: ignore empty change set during DNS delegation (thank you @sandyleo26 !)