Auto close (rebased onto develop)


This is the same as gh-2769 but rebased onto develop.

----

To round out the options (e.g. `--wait_completed`, `--close_completed`, etc) from `import --advanced-help`, `--auto-close` has now been added which calls close on the `ImportProcessPrx` and the `HandlePrx` as soon as possible. This branch was initially intended for 5.1 for which additions were made to the API (`ImportSettings.autoClose`). Since that's not feasible for 5.0.3, this uses a user-annotation with the `NSAUTOCLOSE`namespace. (Later DB upgrades can look for failed auto-closed entries)

To test:
 * `bin/omero import -- --auto_close FILES`
 * Should show "Disconnecting" once upload is finished.
 * In `Blitz-0.log` a statement such as this should be printed:
```
2014-07-08 09:57:51,692 INFO  [    o.s.blitz.repo.ManagedImportRequestI] (2-thread-2) Auto-closing...
```
 * For the keen, import 1000s of images and see if `lsof` is happy.


/cc @bpindelski @ximenesuk @sbesson @mtbc

                
should this be done in this PR?