Integrate the overview material

[dwelsch-esi]

FEATURE REQUEST: Integrate the overview material

Overview

The following reorganization is suggested:

Move the "Architecture" and "Concepts" section to follow the "Introduction" section. Integrate Concepts and Architecture to reference each other's content for a more complete picture of the system.

Context

This issue tracks recommended changes resulting from an analysis of the Litmus Chaos
documentation commissioned by CNCF. The analysis and supporting documents are
here: https://github.com/cncf/techdocs/tree/main/analyses under
0013-litmuschaos.

Possible Implementation

Concepts and Architecture could be integrated into one description of Litmus Chaos. Both are good but separate views into the working of Litmus Chaos. "Architecture" describes the separation of the control and execution planes and provides sequence diagrams of the Chaos processes; "Concepts" describes the logical entities that make up the Chaos process. It would be helpful if these two descriptions referenced each other. For example, a section on a Concept could point out which steps in the sequence diagram the entity is involved in.