Implement annotation to support headers control

[johnlanni]

Why do you need it?

Control http request and response headers with operations such as add, update and delete.

How could it be?

format:

# add or update single header
higress.io/<request|response>-header-control-<add|update>: "foo bar"
# add or update multiple headers
higress.io/<request|response>-header-control-<add|update>: |
  foo bar
  test true
# remove single header
higress.io/<request|response>-header-control-remove: "foo"
# remove multiple headers
higress.io/<request|response>-header-control-remove: "foo,bar"

example:

apiVersion:networking.k8s.io/v1 
kind: Ingress
metadata:
  annotations:
    # add request headers
    higress.io/request-header-control-add: |
      foo bar
      test true
   # add response headers
    higress.io/response-header-control-add: |
      foo bar
      test true
  name: demo
spec:
  ingressClassName: higress
  rules:
    - host: example.com
      http:
        paths:
        -  path: /test
            pathType: Exact
...