Fix: Improve import_fail to accept multiple parameters.
Del: Use reload instead of multiprocessing for more compact, clearer tests.
Docs: Rewrite and improve.
      Move comments to docstrings.
Fix: Clean up unused imports.
Docs: Clean up, move to docstring per coding convention.
Fix: Encoding must be on first or second line of file.
Fix: Skip instead of failing tests which need missing prerequisites.