Cells: Blueprint - improve Goals, Requirements, FAQ, and Deployment plans

Problem

Current Cells blueprint is only vaguely describing all dependencies and workstreams of this project.

Proposal

There's a rising need to better document the following since this information is spread across many sources today:

• Goals:
  • Revisit Goals of the project and split Goals into various categories: Project, Design, Technical to better focus each category.
  • Update project constraints - and link them to prior discussions.
• Deployment:
  • Document Deployment Phases as a way to focus on a deployment requirements, the work currently devided into Workstreams, and Workstream iterations:
  • Each Deployment Phase should document anticipated architecture of the deployment.
  • Each Deployment Phase should document what we achieve and what trade-offs we are making to make this phase to happen.
• FAQ:
  • Gather prior discussions and raised topics into a single searchable section of answered questions.

References:

• https://docs.gitlab.com/ee/architecture/blueprints/cells
• https://docs.gitlab.com/ee/architecture/blueprints/cells/goals.html
• https://docs.gitlab.com/ee/architecture/blueprints/cells/glossary.html