Linkml model seperations

[mahdanoura]

addresses #13 and additionally the following points:

1. separates the TD schema into smaller ones based on the WoT ontologies (td, hctl, wot-security, and jsonschema)
2. removed the config file and changed the interface, because we cannot support everything for now, and for testing it's better to restrict
3. added an extra generation so that one complete LinkML file is created based on the smaller LinkML files. This is suitable for future use, so that users don't have to work with individual files.
4. Improves the classes and attribute definitions
5. Fixed modelling definitions that required Union[List[int], str]

[mahdanoura]

Merged PR on 05.07 as it is getting too large