* Add validating admission webhook HTTP server application
* Handle incoming AdmissionReview requests and validate their correctness, handle errors if any
* Validate Network Attachment Definition objects
* Send AdmissionReview response with allowed/denied decision and its reason
* In case of any other errors (malformed HTTP request, empty body, etc.) send proper HTTP error code
* Use TLS encryption
* Add some basic unit tests for Network Attachment Definition objects validation
* Build Docker image with webhook application
Signed-off-by: Przemyslaw Lal <przemyslawx.lal@intel.com>
