be nitpicky about missing references

Signed-off-by: Alfredo Deza <alfredo@deza.pe>
ensure pybind is in the PYTHONPATH

Signed-off-by: Alfredo Deza <alfredo@deza.pe>
Merge pull request #1527 from ceph/wip-6465

be nitpicky about missing references

Reviewed-by: Sage Weil <sage@inktank.com>