Implement support for scenarios

[johanneshiry]

At the moment we do not support different grid scenarios e.g. with different combinations of enabled or disabled assets within the same grid model. However, this functionality might become a requirement soon.

One way to implement a scenario support would be to post-process a GridContainer with additional information about the asset operation times for different scenarios. Such information could be structured as uuid, operatesFrom, operatesUntil.

This could then be read in after the GridContainer has been build and manipulate all assets accordingly. To avoid the overhead of rebuilding the whole grid, one could also consider include this scenario modification information in the general reading process. However, this would require all connectors to be altered.

Feel free to discuss different approaches below here as well.