Add Chapter - Using Debug info

[spencer-lunarg]

Things like OpLine, OpSource, NonSemantic.Shader.DebugInfo.100, etc are designed to allow SPIR-V generators to add this information into the SPIR-V and then allow tooling to retrieve this information to help map back information from the SPIR-V

It would be useful to have some examples for both

• How to add to your SPIR-V (for code generators)
• How to parse the data out of SPIR-V (for tools)