Add ${aspnet-traceidentifier} (ASP.NET Core only)

[304NotModified]

Fixes #92

[codecov-io]

Codecov Report

Merging #99 into master will not change coverage.

@@           Coverage Diff           @@
##           master      #99   +/-   ##
=======================================
  Coverage   57.04%   57.04%           
=======================================
  Files          25       25           
  Lines         291      291           
  Branches       75       75           
=======================================
  Hits          166      166           
  Misses         90       90           
  Partials       35       35

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