paramiko should be listed in tools/pip-requires

======================================================================
ERROR: Failure: ImportError (No module named paramiko)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/nose/loader.py", line 390, in loadTestsFromName
    addr.filename, addr.module)
  File "/usr/lib/python2.7/dist-packages/nose/importer.py", line 39, in importFromPath
    return self.importFromDir(dir_path, fqname)
  File "/usr/lib/python2.7/dist-packages/nose/importer.py", line 86, in importFromDir
    mod = load_module(part_fqname, fh, filename, desc)
  File "/opt/tempest/tempest/tests/boto/test_ec2_instance_run.py", line 27, in <module>
    from tempest.common.utils.linux.remote_client import RemoteClient
  File "/opt/tempest/tempest/common/utils/linux/remote_client.py", line 4, in <module>
    from tempest.common.ssh import Client
  File "/opt/tempest/tempest/common/ssh.py", line 30, in <module>
    import paramiko
ImportError: No module named paramiko

This was after pip install -r tools/pip-requires