One feature of the new private-module layout is that a python
script cannot simply 'import ganeti'. The reason is that the
interfaces to these modules are not stable and hence should not
be used outside Ganeti. However, this is what the burnin test
in the qa does. The good news is that we know that the burnin
script will always be from the same version of ganeti as the
one we're testing against; so we can simply provide the appropriate
PYTHONPATH.

Signed-off-by: Klaus Aehlig <aehlig@google.com>
Reviewed-by: Jose Lopes <jabolopes@google.com>