Initial setup for Labradoor

Labradoor will be a library that can be used by Queue and CPM2.0
to allow for easy configuration of Spring Security to connect to
the TUD SAML or some in-memory authentication provider.

Additionally, labradoor will allow 'the door' to Labracore in the
form of an API specification and the implementation of such a spec.
This implementation is done through the OpenAPI generator plugin for
gradle.