rename test_harness.py to test_fixture.py

See GitHub Issue #84.

Signed-off-by: Erik Bernoth <erik.bernoth@gmail.com>
test_fixture.py: rename references to fixture

See GitHub Issue #84.

Signed-off-by: Erik Bernoth <erik.bernoth@gmail.com>
rename test data files

See GitHub Issue #84.

Signed-off-by: Erik Bernoth <erik.bernoth@gmail.com>