Add Python client module

This module provides mostly the same inteface as the "pynsca" module for
the traditional NSCA protocol.
Move src/python to top-level directory

Don't hide the Python module in a subdirectory, at least not as long as
we don't integrate it with our build system.
Let Git ignore the python/build directory
Update python/uthash.h

Grab the current version from the uthash repository (commit ID:
fe01a6ad1bf5fa722930d074fd41d0214d351a7e).
Add python/Makefile.am file

Include the Python module with our source tarballs.
python/README: Apply cosmetic changes

Change a few details in the README file of the Python module, such as
the indentation and host names in the example code.
Python module: Change code formatting

Change the coding style of the Python module for consistency with the
rest of our code.
Merge branch 'python'

* python:
  Python module: Change code formatting
  python/README: Apply cosmetic changes
  Add python/Makefile.am file
  Update python/uthash.h
  Let Git ignore the python/build directory
  Move src/python to top-level directory
  Add Python client module