* Add DDI Authentication (using apikey)
* Gateway token by passing as apikey "GatewayToken: <token>"
* Target token by passing as apikey "TargetToken: <token>"
* Removed Bearer auth as not supported
* Authentication schemes are set to the correspondent groups in order to be visible only where needed
* Optional OpenAPI (with property _hawkbit.server.swagger.enabled_, by default _true_)
Signed-off-by: Marinov Avgustin <Avgustin.Marinov@bosch.com>