Add dynamic components to the data definition

[TimoWolters]

The static data definition is already implemented as part of the LotsenApp. The dynamic components should enable authors to add initial values to data fields, perform calculations based on other values, create documents as part of documentation events, create groups as part of documents.

In general a language is required that allows for data manipulation on the static objects of the data definition.

An initial approach may use LUA or another embeddable scripting language. Calculations should be done entirely in the backend.