SCOPED_TIMER is a QA-only simpler version of PROF_COUNTER.
Extend PROF_COUNTER to allow access to the std::chrono::duration
for more flexibility.
Wrap PROF_COUNTER in SCOPED_PROF_COUNTER for RAII duration
output (for the same effect as SCOPED_TIMER).
Move into own include directory for clarity. Also allows qa_utils
to use its own private headers in qa/qa_utils without exposing them
through the target_include_directories directive.