Add an FAQ and/or high-level overview of how to integrate TUF

We are often asked the same questions regarding delegations, how to organize TUF metadata, key management, etc. There should be an FAQ page for these sorts of questions.

The Survivable Key Compromise paper provides an overview of TUF's design, and the specification and other documents available here capture most of what it contains. However, the integration side of things is not adequately explained outside of the Diplomat and Mercury papers. The PEP 458 document is also a good resource for how to integrate TUF with an existing software updater and community repository.

We should provide a condensed, high-level document that contains the information in the papers and documents that have been written since the Survivable Key Compromise paper.

审阅 Survivable Key Compromise、Diplomat 和 Mercury 论文，以及 PEP 458 文档和现有的 TUF 规范材料。将其中的集成指导整理成一份精简的 FAQ 或高级概览，涵盖委派、元数据组织和密钥管理；当一份易于理解的文档解释了反复出现的集成问题时，即视为完成。