Rocket 0.4.1发布,Docker容器替代品

Rocket 接连发布两个版本，0.4.0 和 0.4.1，其中 0.4.0 与 0.3.2 版本比较改进内容包括：

• Updated to v0.4.0 of the appc spec

• Introduced a database for indexing local images in the CAS (based on github.com/cznic/ql)

• Refactored container lifecycle to support a new "prepared" state, to pre-allocate a container UUID without immediately running the application

• Added support for passing arguments to apps through the rkt run CLI

• Implemented ACI rendering for dependencies

• Renamed rkt metadatasvc -> rkt metadata-service

• Added documentation around networking, container lifecycle, and rkt commands

而 0.4.1 则修复了 0.4.0 的如下 bug：

• Fix marshalling error when running containers with resource isolators

• Fixup help text on run/prepare about volumes

• Fixup permissions in rkt trust created files

• Introduce the rkt install subcommand