This introduces and "Open Infrastructure" page which is designed for a
moderately experienced developer with some understanding of Zuul,
Ansible and basic Linux admin skills to have an entrypoint to
navigating the system-config and related repositories.
It is designed to re-enforce the idea of open infrastructure, and
explain how development, testing and production come together at a
level high enough to be understood, but with links or descriptions of
specific places in the code to get started.
It moves a little of what was in the sysadmin page into this, and
leaves that page as more low-level descriptions of various tasks.
Change-Id: I60a9299df455b98ad549ac0075a59d381722bc06
4c86706e5e