Automatic merge from submit-queue
Improvements on OpenAPI spec generation
- Generating models using go2idl library (no reflection anymore)
- Remove dependencies on go-restful/swagger
- Generate one swagger.json file for each web-service
- Bugfix: fixed a bug in trie implementation
Reference: #13414
**Release note**:
```release-note
Generate separate OpenAPI spec for each API GroupVersion on /<Group>/<Version>/swagger.json
```