DigitalOcean.com开放了应用市场，开发者可以提交镜像。
参考：https://marketplace.digitalocean.com/vendors/getting-started-as-a-digitalocean-marketplace-vendor
参考：https://github.com/digitalocean/marketplace-partners/blob/master/marketplace_docs/build-an-image.md
参考：https://github.com/digitalocean/marketplace-partners