Update-conf-py

-----

- Python3 compatibility changed to 3.3 or newer (including Python 3.5).

-----

- Python 3 (3.2 or newer) compatibility added;
- Improvements in the build process;
- `CONTRIBUTING.md` added and a fix in `README.md`.

-----

- Python 2.6 compatibility added;
- Project integrated with Travis and Coveralls;
- It passes in all tests (Python 2.6 and 2.7) and has 100% code coverage.

-----

- Docs about config files added.
- **Fix:** More bugs while installing in Linux;
- `MANIFEST.in` created so the required files are now in the source distribution (used by Linux).

-----

- **Fix:** Some bugs while installing in Linux;
- Fixed logic to install `{prefix}/share/update-conf.py` and `/etc/update-conf.py.conf`.

-----

- It's possible to use a user home config file (`~/.update-conf.py.conf`);
- **Fix:** Skip copy of system config file (`/etc/update-conf.py.conf`) when installing using a non-privileged user;
- Project data in `{prefix}/share/update-conf.py`;
- For now, only the sample config file is being put there.