Improve ItemTable component

[sven-n]

Is your feature request related to a problem? Please describe.
The ItemTable component just shows the Name-Property or ToString-Representation of an object, see ObjectExtensions.GetName(...).
For example, it would be nice to see the monster level in a list of monsters, too.

Describe the solution you'd like
It should be possible to define which additional properties should be visible in the table. Maybe with Attributes on the required properties in the data model classes.