Only include relevant files in test directory.
Only include relevant files in test directory.

Previous releases contained runtime artifacts due to a greedy machting
recursive-include statement:

    w3lib-1.16.0/tests/__pycache__/test_encoding.cpython-27-PYTEST.pyc
    w3lib-1.16.0/tests/__pycache__/test_form.cpython-27-PYTEST.pyc
    w3lib-1.16.0/tests/__pycache__/test_html.cpython-27-PYTEST.pyc
    w3lib-1.16.0/tests/__pycache__/test_http.cpython-27-PYTEST.pyc
    w3lib-1.16.0/tests/__pycache__/test_url.cpython-27-PYTEST.pyc
    w3lib-1.16.0/tests/__init__.pyc

It is better to use explicit patterns for inclusion.

scrapy/w3lib