AIT:Added a refresh() function for Fabrics.
AIT:Added a refresh() function for Fabrics.

Sometimes when tests power on/off systems or MC_RESET node IPs change.
We want the ability to get the new ips for the current fabric object
without a complete re-init.
Cynerva/cxmanage,SilverLiningSystems/cxmanage-test,SilverLiningSystems/cxmanage-test,SLS-Dev/cxmanage,SLS-Dev/cxmanage,SilverLiningSystems/cxmanage-test2,SilverLiningSystems/cxmanage-test2,Cynerva/cxmanage