Removed threaded operation entirely to help travis tests to work.

It's better that way, as it's time to see that async doesn't do what
it was meant to do, at least not in multi-threaded mode.

setup.py: added zip_safe flag

Fixing issues with easy_install in setup.py to allow async to be easy…

…_installed. Its a mess, but I didn't expect anything else. Having everything in one directory really is not what they want ...