feature: multi user support and access control based on RBAC

[nitisht]

This includes following items

• Multi user support --> Done with PR Add multi user support #409
• Authorisation mechanism based on roles setting per user --> Done with PR Add role based authorization #417
• Integration tests in Quest --> PR Add basic rbac test quest#21
• Documentation
• High CPU usage in hashing. Need to change to another hashing approach. --> Refactor auth flow  #425
• List user roles API --> GET {{endpoint}}/api/v1/user/{{username}}/role --> Refactor auth flow  #425
• Label based access for reader privilege --> Query filter #429