added missing setup.py which blocks pip install

When trying to install the sssapi using pip you consistently get

```
Obtaining python-sdk from git+https://github.com/snowshoestamp/python_sdk.git#egg=python_sdk
  Updating /Users/rosscdh/.virtualenvs/toolkit/src/python-sdk clone
  Running setup.py egg_info for package python-sdk
    Traceback (most recent call last):
      File "<string>", line 16, in <module>
    IOError: [Errno 2] No such file or directory: '/Users/rosscdh/.virtualenvs/toolkit/src/python-sdk/setup.py'
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):

  File "<string>", line 16, in <module>

IOError: [Errno 2] No such file or directory: '/Users/rosscdh/.virtualenvs/toolkit/src/python-sdk/setup.py'
```

this is caused by the missing setup.py which also defines how python should link in the package.

1. added missing setup.py with some default values (please review the values)