add alternate setup.py impl
Support alternate build as proper CPython extension, and/or by distutils

uWSGI will instruct setuptools to generate a console_scripts entry_point as
bin/uwsgi, and will in general behave more like a normal extension.
Also exports uwsgi.ORIG_ARGV and uwsgi.NEW_ARGV... ex. usage:

    # python -i -c \
        'import uwsgi as u; u.setup().worker_id()==1 or u.run()' \
        --master --workers=1 --enable-threads --honour-stdin \
        --auto-procname --http :8000

Relies on new_argc/new_argv support in 2.1