(PUP-659) Optimize qualified variables

This optimizes resolution of qualified references. It turned out that the resolution process
was still following the old rules of "dynamic scope" as well as handling removed/unused features (such as
giving scopes multiple name-spaces). This enabled the removal of code that caused resolution of
non absolute references.

This PR also includes other tweaks on the involved code path (avoiding calls to debugging with
semi expensive construction of interpolated strings, etc.)-