Number of VNF ports

[ivanocerrato]

Currently, the name resolver indicates the max number of ports of a VNF (this info shuld be put in the VNF template, but this is another story).
When a new graph is going to be deployed, the unorch checks that the number of required ports does not exceed that specified in the name resolver.
In case of graph update, this check is instead not done, then it allows the deployment of more ports than those available for that VNF according to the name resolver. This causes a crash in the unorch.