Make Hukz Kubernetes Native and extend the functionality using CRDs

[deshetti]

I am thinking we could provide the following two Kubernetes CRDs that can extend the features of Hukz:

• Provider (Slack, Google Chat, Teams, Sendgrid etc) that defines the required fields of a specific provider like endpoints, auth, message structure etc.
• Application (Dega, Kavach etc) that defines the message structure of the input messages.

Then we can deploy Consumer Resource of type Provider for each consumer. This provides mapping for the fields from the input message to desired provider object, endpoints, auth etc.

This way we don't have to hardcode any application-related or provider-related data into Hukz and can extend it to any application or provider.