Add setup.py

Signed-off-by: Tomas Sedovic <tomas@sedovic.cz>
Make the Clients class directly available

Instead of `from deltacloud_heat.client import Clients` we can now say
`from deltacloud_heat import Clients`.

Signed-off-by: Tomas Sedovic <tomas@sedovic.cz>
Update README and convert it to reStructuredText

We can now use the README in setup.py as `long_description` and have it
appear in PyPI.

Signed-off-by: Tomas Sedovic <tomas@sedovic.cz>
.gitignore the build artifacts

Signed-off-by: Tomas Sedovic <tomas@sedovic.cz>