Description of problem:
When admin/user is using long lasting actions like:

import/export of template/VM
creation of VM from template
creation of template from VM
migration of VM/template disk

which might last significant amount of time, it would be good to 
inform user//admin somehow about the status of the action, like ETA or 
how many percent of action is done.

I'm not sure if it's possible for all those actions but it would be 
a nice feature for admin/user to know.

Idea came from exporting of VM from storage domain which consume
significant amount of time and when user(myself) wanted to provide export
domain to other user but had to wait to finish transaction.