Cloud View: slow connections: tree should inform user that it is still loading

how to reproduce:

1) make sure you have a connection to a deltacloud server that is connected to your ec2 account
2) make sure you have an instance on ec2 (running or not)
3) go to the cloud view: open the instances branch

Result:
It is initially empty (although you have a running/stopped instance). If you wait for a while it will suddently appear.

Expected result:
The branch should show an child "retrieving...." (like in SVN/CVS explorer) and update the branch as soons as the instances are retrieved from ec2