setup.py: exclude all test files
setup.py: exclude all test files

by using exclude feature of find_packages.
Plus remove now obselete package_data setting

Signed-off-by: Konrad Weihmann <237a31e24baec6fd7412e435f5dfb93997617781@outlook.com>

gitpython-developers/GitPython,gitpython-developers/gitpython,gitpython-developers/GitPython,gitpython-developers/gitpython