Unwrap namespace (rebased onto develop)



This is the same as gh-1532 but rebased onto develop.

----

This began with a very small change to `script_utils.py`, namely fixing the following error:
```
	*** start stderr (id=202)***
	* Traceback (most recent call last):
	*   File "./script", line 80, in <module>
	*     runAsScript();
	*   File "./script", line 75, in runAsScript
	*     initialise(session)
	*   File "./script", line 65, in initialise
	*     script_utils.registerNamespace(iQuery, iUpdate, NAMESPACE, keywords);
	*   File "/opt/ome2/dist/lib/python/omero/util/script_utils.py", line 1175, in registerNamespace
	*     workflow = iQuery.findByQuery("from Namespace as n where n.name = '" + namespace.val+"'", None);
	* AttributeError: 'str' object has no attribute 'val'
	* 
	*** end stderr ***
```
when running the `FLIM_initialise.py` script.

The other commits are all tidying the file afterwards.