Debugging extension

[axic]

This was discussed in the past (first year), but we haven't actually recorded any proposal.

Goal: store debugging information as a section(s) in EOF.

This information is not acceptable on-chain, and so must be stripped prior to deployment, but EOF could allow carrying this information from the compiler to frameworks/tooling, and getting removed prior to the deployment process.

Since we have individual sections for functions, we should first of all store a "names section", which defines the function names and inputs and output for each function. The names section in WebAssembly is a good inspiration. It should be also possible to further introduce the storage of variable level information, based on the work done by the ethdebug workgroup.