Switch to CircleCI 2.0

We should switch our build process over to CircleCI 2.0.

We can then run a pipeline that works like the following:

- compile
- test
- maybe deploy
- to `staging`
- to `remote-development`
- to `production`
- API blueprint docs
- inline Elixir docs

该 issue 未指定任何文件或测试；首先定位现有的构建配置，以及用于编译、测试和部署的入口点。将这些步骤映射到提议的 CircleCI 2.0 流水线，并确认 staging、remote-development、production、API Blueprint 文档和内联 Elixir 文档都已涵盖。

由索引模型根据 Issue 内容生成。