Fix python3 compatibility

Fix Module imports
Replace deprecated dict.has_key call
Use print functions
Alias xrange for range in python3 where they do the same thing
Alias basestring for python3 which combines unicode and str into str
Split __cmp__ into __lt__ and __eq__because __cmp__ is deprecated in python3
Replace operations.div by operations.truediv because the prior is deprecated in python3
Add requirements file for pip install -r requirements.txt which is pretty standard for python projects.
Add language classifier information
Set zip_safe=False to avoid errors while installing