Update for Version 7 export
The NIS CIM Version 7 export has many changes, of which the following affect the CIMScala reader:
- add Jumper to handle Trenmesser (a metal jumper in a fuse holder used to connect/disconnect a feeder)
- add Conductor for reference connections (virtual connections between overhead and underground)
- PowerTransformerEnd replaces the more complex modelling with TransformerTank and TransformerTankEnd