- default enviroments for prod, test stage
- used defaults env can just be referenced via name in config.yaml
- custom envs can be added dynamically 

- only throw runtime exceptions on all client calls
- wrap all internal exceptions to 4 defined exceptions the user has to deal with

* load schema from specified path on initiation
* fixed and adjusted tests

* added loading of submission data schema
* added submission data validation to sender and subscriber flow
* added and adjusted tests and test data
* added attribute for skipping validations to config, fixed tests

added checks of schema URI and MIME type based on available destinations, adjusted and extended tests

- Neuer Routing Client
- Zugriff auf findDestinations und findAreas der Routing API
- Validierung der Signaturen und Claims der Routen-Signaturen
- Handling von detached-signatures (Hinzufügen des detached payloads)