xml: added helper to modify (shared) xml location
Merge pull request #355 from mtomaschewski/xml-location-modify

xml: added helper to modify (shared) xml location
bridge: added function to calculate bridge wait time

When STP is enabled, the bridge may need up to 50sec
(using defaults) longer to become ready and forward
traffic than without STP and we have to consider this
additional time in timeout calculations.
Merge branch 'master' into testing