Topology name with spaces breaks the exporter

[SaturnHafen]

Description

When trying to export a Topology with a topology.name attribute containing a space, the exporter gets confused and is unable to fully write the scenario.
We should probably sanitize the input by replacing chars not common / forbidden in filenames (like , /, \, ...) with something like _. Alternatively, we could quote the filenames when passing them to the methods in question.

Steps to reproduce:

1. Create (e.g. import) a topology
2. set topology.name to a string containing a white space
3. export the topology