Change Network Topology panel so it stops polling ajax on error

Change javascript so that we don't use interval that will always call
AJAX, instead only schedule next AJAX poll when we have successfully
finished the previous AJAX request.
This avoids many calls with errors if token times out.

Fixes bug #1253768

Change-Id: I74c4bf8cb931655ce64783ae11467183275386ab
Merge "Change Network Topology panel so it stops polling ajax on error"