update docs for karate-mock-servlet

Author: ptrthomas

karate-mock-servlet/README.md

@@ -22,22 +22,14 @@ So yes, you can test HTTP web-services with the same ease that you expect from t
 ```
 
 ## Switching the HTTP Client
-Karate actually allows you to switch the implementation of the Karate [`HttpClient`](../karate-core/src/main/java/com/intuit/karate/http/HttpClient.java) even *during* a test. For mocking a servlet container, you don't need to implement it from scratch and you just need to over-ride one or two methods of the mock-implementation that Karate provides.
+You can completely customize the HTTP client used by Karate by implementing the [`HttpClient`](../karate-core/src/main/java/com/intuit/karate/http/HttpClient.java) interface which happens to be very simple.
 
-> If you need to create a completely new `HttpClient` implementation from scratch, the [`MockHttpClient`](src/main/java/com/intuit/karate/mock/servlet/MockHttpClient.java) is a good reference. There are many possibilities here, you can add support for other HTTP clients besides Apache and Jersey, or mock a stack that is not based on Java servlets.
+If you need to create a completely new `HttpClient` implementation from scratch, the [`MockHttpClient`](src/main/java/com/intuit/karate/mock/servlet/MockHttpClient.java) is a good reference. There are many possibilities here, you can add support for other HTTP clients besides Apache and Jersey, or mock a stack that is not based on Java servlets.
 
-Let's take a closer look at the following [`configure`](https://github.com/intuit/karate#configure) keys:
-
- Key | Type | Description
------- | ---- | ---------
-`httpClientClass` | string | The class name of the implementation you wish to use. By default the Karate Apache (or Jersey) HTTP client is used. You need a zero-argument constructor. If you need more control over construction, refer to the next row.
-`httpClientInstance` | Java Object | A fully constructed instance of an `HttpClient` implementation. Useful if you need more dynamic control over things like dependency-injection.
-`userDefined` | JSON | You normally would not need this general-purpose extension mechanism where you can pass custom JSON data to the HTTP Client instance via the [`configure`](https://github.com/intuit/karate#configure) keyword. Refer to [this test](../karate-core/src/test/java/com/intuit/karate/http/HttpClientTest.java) for an idea of how you can use this for advanced needs, such as if you wanted to customize your HTTP Client implementation *during* a test.
+Karate defaults to the [`ApacheHttpClient`](../karate-core/src/main/java/com/intuit/karate/http/ApacheHttpClient.java), and to change this for a test-run, you can set the [`HttpClientFactory`](../karate-core/src/main/java/com/intuit/karate/http/HttpClientFactory.java) using the [`Runner`](../karate-core/src/main/java/com/intuit/karate/Runner.java) "builder" API.
 
 ## Mocking Your Servlet
-You only need to over-ride two methods: 
-* `Servlet getServlet(HttpRequestBuilder request)`
-* `ServletContext getServletContext()`
+Creating a `Servlet` and `ServletContext` instance is up to you and here is where you would manage configuration for your web-application. And then you can implement `HttpClientFactory` by using the `MockHttpClient` code provide by Karate.
 
 Once you refer to the following examples, you should be able to get up and running for your project.
 * Spring MVC Dispatcher Servlet
@@ -47,10 +39,7 @@ Once you refer to the following examples, you should be able to get up and runni
 
 Note that the first example above tests the whole of the [`karate-demo`](../karate-demo) Spring Boot application, and using a [parallel runner](src/test/java/demo/MockSpringMvcServletTest.java)
 
-## Configuration
-Everything is typically tied together in [bootstrap configuration](https://github.com/intuit/karate#configuration). If you do this right, your `*.feature` files can be re-used for mock as well as *real* integration tests.
-
-Use the test configuration for this `karate-mock-servlet` project as a reference: [`karate-config.js`](src/test/java/karate-config.js)
+If you structure your tests propertly, your `*.feature` files can be re-used for mock as well as *real* integration tests.
 
 ## Limitations
 Most teams would not run into these, but if you do, please [consider contributing](https://github.com/intuit/karate/projects/3#card-22529274) !