Add HTTP Extractor

[ishanarya0]

Build a generic HTTP extractor.

A sample config

source:
  name: http
  config:
    request:
      host: http://example.com
      method: POST
      path: /v1/employees
      encoding: json
      query:
        foo: bar
      body: {
        "fieldA": "valueA",
        "nestedField": {
          "fieldB": "valueB"
        }
      }
    response:
      model: user
      mapping: // explore with jsonpath
        urn: 
        name: "name"
        age: "profile.age"
        array:
          - id: "array[].id"
            name: "array[].name"
        data:
          attributes:
            foo: "nested.foo"
      expected_codes:
        - "200"
        - "201"
      retry_codes:
        - "500"
        - "503"