Proposal: Every time we use an environment variable or a global property, we should mark it as used, so that we can log which variables were actually consumed during the build.

This would be very useful to determine the "closure" of the build where it depends on the environment. For example, people may inadvertently rely on the "Version" variable, and CI may set that, causing undesired side effects.

Several times now I've seen VSTS CI build breaks because the codebase assumed that Version is of a certain format, and CI was setting it to something else.