docs: Use proper avocado version string upon build

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Merge pull request #23 from avocado-framework/avocado-docs-version

docs: Use proper avocado version string upon build
avocado: Fix mistakes in copyright headers

I went through all python files in avocado code, and
some changes were made:

* Files entirely written by the current avocado dev
team were changed to be GPL v2+
* Files with a significant portion of code derived
from autotest remain GPL v2 strict, and original
authorship was re-established

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Merge pull request #24 from avocado-framework/fix-copyright-headers

avocado: Fix mistakes in copyright headers
plugins.xunit: Add class XmlResult.

Improvements for using xUnit  with Jenkins (Junit).
Now the actual XML result is handled in class XmlResult.
Also minor fix (cosmetics) in tests.failtest.

Signed-off-by: Ruda Moura <rmoura@redhat.com>