Fix storing binaries in Swift

 * Swift does not work with Keystone API v3, so we need to always provide
   auth_url for API v2 to Swift.
 * We incorrectly parsed swift URL, which resulted in Sahara trying
   to get binaries from containers with '.sahara' suffix, while the
   suffix should be stripped.

Closes-Bug: #1305210
Change-Id: I76dee756165e089bc408e584f3aa476c45ed6067
(cherry picked from commit 9ad556f5984510b843b2b52c127af2fa804d98cf)