Use new sqlalchemy and jinja2
    
    Use the pkg_resources WorkingSet method to make sure we have
    a reasonably sane version of sqlalchemy and jinja2 on systems
    where the old version is primary, but the new version is installed.
    
    Signed-off-by: Patrick Uiterwijk <puiterwijk@redhat.com>
    Reviewed-by: Pierre-Yves Chibon <pingou@pingoured.fr>
    Reviewed-by: Howard Johnson <merlin@merlinthp.org>