HermeneutiX: allow multi-language configuration of semantic relations

[CarstenWickner]

As a HermeneutiX user I want to be able to define the same semantic relations/roles in multiple languages, in order to be able to export the same analysis for varying target languages/contexts.

One option would be to have multiple sets of relation models and allow switching between them.
Another option could be to split out the configuration of semantical roles from the relation setup and cater for multiple sets/profiles of translations for those roles.

This is based on the suggestion from Phil (@j2l) for Issue #14.

[CarstenWickner]

For this, the overall configuration of relations needs to be simplified/cleaned up, before adding even more complexity with those alternative languages (however that's supposed to be handled).
I'm open for design suggestions.

[CarstenWickner]

The overall approach should pretty much follow what is being done for #14 (syntactic functions). But since the semantic relations are currently not part of the file structure and only dependent on whatever is configured in the respective instance of SciToS/HermeneutiX, some adjustments will be required. I.e. probably need to rely on the relations defined in an opened file and only apply the configured semantic relations on new projects (as for the syntactic functions) instead of always offering the configured relation options.