suite: fix build_matrix when non-yaml present in % dir

First, if we get a non-yaml file, return an empty list.

Second, if we are in a % mode, exclude an empty raw result from the
combination.  Otherwise, we get no resulting jobs.

Signed-off-by: Sage Weil <sage@redhat.com>
Merge pull request #304 from ceph/wip-fix-build-matrix

suite: fix build_matrix when non-yaml present in % dir
Tweak usage statement

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
add an initial version to teuthology

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
pull the version and description in setup.py

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
create a --version flag for teuthology

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
Merge pull request #305 from ceph/wip-8640

implement `--version` and improve `setup.py`
Remove most ceph-specific tasks. They are in ceph-qa-suite now.

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
Correctly find both internal and external tasks

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>