Todo
  * FIXME: More -dry-run checks for object transfer
  * Ignoring the pseudo directories
    * if object.PseudoDirectory {
      * fmt.Printf("%9s %19s %s\n", "Directory", "-", fs.Remote())
  * Make Account wrapper
    * limit bandwidth for a pool of all individual connectinos
    * do timeouts by setting a limit, seeing whether io has happened
      and resetting it if it has
    * make Account do progress meter
  * Make logging controllable with flags (mostly done)
  * -timeout: Make all timeouts be settable with command line parameters
  * Check the locking in swift module!
  * Windows paths? Do we need to translate / and \?
  * Make a fs.Errorf and count errors and log them at a different level
  * add -modify-window flag - fs should keep knowledge of resolution

Ideas
  * optimise remote copy container to another container using remote
    copy if local is same as remote
  * Allow subpaths container:/sub/path
  * look at auth from env in s3 module - add to swift?

Need to make directory objects otherwise can't upload an empty directory
  * Or could upload empty directories only?
  * Can't purge a local filesystem because it leaves the directories behind

s3
  * Can maybe set last modified?
    * https://forums.aws.amazon.com/message.jspa?messageID=214062
    * Otherwise can set metadata
  * Returns etag and last modified in bucket list