Add Jetty 12 supporting documentation (#271)

Signed-off-by: Andriy Redko <[email protected]>

_docs/getting-started.md

@@ -18,6 +18,7 @@ At the moment, we provide the following quick starts for beginners:
 
 - [API Mocking with Java and JUnit 4](../quickstart/java-junit)
 - [Downloading and Installing WireMock](../download-and-installation)
+- [Using WireMock with Jetty 12](../jetty-12)
 
 <!-- TODO: Add standalone in Docker -->
 

_docs/jetty-12.md

@@ -0,0 +1,62 @@
+---
+layout: docs
+title: "Using WireMock with Jetty 12"
+meta_title: Using WireMock with Jetty 12 | WireMock
+description: WireMock ships with Jetty 11 by default but fully supports Jetty 12 as well.
+---
+
+WireMock ships with Jetty 11 by default but fully supports Jetty 12 as well with a new module `wiremock-jetty12`. In this tutorial we are going to see how Wiremock could be configured to use Jetty 12.
+
+## Prerequisites
+
+- Java 17
+- Maven or Gradle, recent versions
+- A Java project, based on Maven or Gradle
+
+## Add WireMock Dependency to your project
+
+{% codetabs %}
+
+{% codetab Maven %}
+
+```xml
+<dependency>
+    <groupId>org.wiremock</groupId>
+    <artifactId>wiremock-jetty12</artifactId>
+    <version>{{ site.wiremock_version }}</version>
+    <scope>test</scope>
+</dependency>
+```
+
+{% endcodetab %}
+
+{% codetab Gradle Groovy %}
+
+```groovy
+testImplementation "org.wiremock:wiremock-jetty12:{{ site.wiremock_version }}"
+```
+
+{% endcodetab %}
+
+{% endcodetab %}
+
+## Limitations
+
+There are few limitations that usage of Jetty 12 is imposing with respect to stubbing behavior.
+
+- status message will not be returned to the client even if set by the stub explicitly
+    ```java
+        stubFor(get("/my/resource")
+            .willReturn(status(400)
+                .withStatusMessage("ERROR")));
+
+        URI uri = URI.create(wireMockRule.url("/my/resource"));
+        HttpURLConnection connection = (HttpURLConnection) uri.toURL ().openConnection ();
+        connection.setRequestMethod ("GET");
+
+        assertThat(connection.getResponseCode()).isEqualTo(400);
+        assertThat(connection.getResponseMessage()).isEqualTo("Bad Request"); /* the status message is not returned */
+    ```
+- when using multipart form data, the body is not decoded into plain text in case of `base64` (or other encodings) 
+
+- serving files from configured file locations always ends up with redirect when folder (without trailing `/`) is requested