pip installable and more modular

I substituted setuptools for distutil: 

This made it so setup.py could use the install_requires arg. 

The install_requires arg made it lib/paramiko, lib/python2/httplib2, lib/python3/httplib2  didn't need to be there.

Getting rid of those made it so you don't have to maintain them in this repo. 

I also pulled the "import manta" out of the setup script as it was only used to set the version. This enable install_requires to actually install the dependencies. Otherwise it would fail because the dependencies weren't installed.

You shouldn't have to care about python2 vs python3 as a matter of installation anymore... 

`pip install git+http://github.com/deserat/python-manta.git` works now. 
`easy_install .`
`python setup.py install`  all work.

Those are by far the most common methods of installation in the python world.

If one isn't using SmartOS there is no need to pre-install pycrypto... it just gets installedt.
If one is using SmartOS you still need to `pkgin install py-crypto`. cause well... you know.

I think this gives you the best of both worlds but if you hate it... just reject it. I'll only cry a little. :)