Converted NetworkModel to Property observer pattern
Corrected GRaphicModel to use propertyChangeEvents
Added creation check in GraphicModel
Converted all models to propert observer pattern
Merge branch 'master' of https://github.com/atrakeur/SIRES into vl_obspattern
Bring up to date with master
Corrected link creation
Merge pull request #2 from atrakeur/vl_obspattern

Vl obspattern