Initial conformance profiles and reporting prototype

[shaneutt]

This is a sub-issue of #1709 to start prototyping the GEP in it's current step so that we can test and try out some of the ideas we have so far and see how they work. The result that should be produced are non-released (not accessible by end-users of the go library unless explicitly opted in to) tools for running profiles and producing a ConformanceReport.