Add doctest for old style classes.

Descriptors are invoked via the __getattribute__ method, which is only
available for new-style classes. Therefore old style classes require
extra testing. See:

http://docs.python.org/2/howto/descriptor.html#invoking-descriptors
Fix old-style classes [HOT]
Convert README to reST

Currently, PyPI supports only reST as markup format while GitHub can
live with both markdown or reST, so it's easier to use reST.

In setup.py we can now assume that README.rst exists since it is
included in the source distribution via MANIFEST.in.
Convert LICENSE to reST as well

Its simpler to have only one markup format present in the project.
Use unix line endings in setup.py and MANIFEST.in and mode 644 in setup.cfg

Nobody wants DOS line endings. Best compare with:

    git diff --ignore-space-at-eol
Merge pull request #19 from coldfix/reST

Use reST format for README and LICENSE
Merge branch 'master' into hotfix-oldstyle-classes

Conflicts:
	setup.cfg

This branch has been pending for a while, thus a merge of the current master
branch was required for conflict resolution.
Merge branch 'hotfix-oldstyle-classes'