CLI Python Packagify

This a series of commits designed to allow our CLI to be packaged and distributed through the Python Package index.  Like Rubygems, PyPI is the standard Python distribution channel and will allow users to install the CLI directly with easy_install or pip onto a system or virtualenv at their leisure.

The PR contains:

- moving locale files under locale/ and inside individual locale directories to follow the server layout and standard layout for internationalization
- updates to the spec file to reflect the changes to locale files
- adds a setup.py which can be used to do:
    - python setup.py install
- KATELLO_CLIENT_CONF_DIR environment variable so that users installing via non-RPM can more easily use define what their configuration is

Post PR acceptance, the katello-cli package would be registered with PyPI and then available for consumption (ideally across platforms).

Testing:
  - tito build --test --rpm passed
  - python setup.py install
  - export KATELLO_CLIENT_CONF_DIR=~/workspace/client.conf
  - katello -u admin -p admin ping (success)