When deploy by IPA on devstack, error message without SWIFT_ENABLE_TEMPURLS is "SWIFT_ENABLE_TEMPURLS must be True to use agent_ssh driver in Ironic.". But this error occurs not only using agent_ssh driver, but also using agent_ipmitool. This patch set fixes this error message to "SWIFT_ENABLE_TEMPURLS must be True to use agent_* driver in Ironic.". Change-Id: I21ce85d00485037d5c86dcd28aa1c95d6dc308b7