Explain what f-r does for Maven projects (#81)

README.md

@@ -671,6 +671,26 @@ edit the web application files in src/main/webapp and see the changes in your
 browser without the need to restart your Frank!. A small example can be found
 in [Frank2Example4](#frank2example4).
 
+When you write a webapplication with Maven, your `pom.xml` file defines how the
+application should be packaged. The Maven build is then typically what you need
+for production. During local development, the Frank!Runner helps you to deploy
+your application in Tomcat. The Frank!Runner then configures the following in
+Tomcat, allowing you to omit it from your `pom.xml`:
+
+* The Frank!Runner adds a database driver for the h2 database in Tomcat's `lib`
+folder. The Frank!Runner also adds a `context.xml` to allow access to a h2
+database.
+* The Frank!Runner adds `geronimo-jms_1.1_spec.jar` to Tomcat's `lib` folder.
+This file should not be packaged in your WAR because it should be provided by
+application servers according to the Jakarta EE standard. Tomcat does not
+provide this file however and hence this library has to be added.
+* The Frank!Runner configures `catalina.properties` to define a scenarios root
+directory for Larva. The Frank!Runner configures the absolute path to
+`src/test/testtool`.
+* The Frank!Runner configures in `cataline.properties` that `dtap.stage=LOC`.
+This way, you can access your webapp through http during development. If you do
+not set `dtap.stage` in your packaged application, it is up to the system
+administrator of the user to configure `dtap.stage`.
 
 # Root CA certificates