New documentation for development tools

docs/composer/plugin/d4d/index.md

@@ -104,6 +104,7 @@ Note that Solr, Node and Varnish are not enabled by default. See the [customizat
 ### PHP Debugging
 
 By default, PHP is configured with XDebug being enabled and you should check the instructions for your IDE on how to get started with a debugging session.
+For the IDE's IntelliJ and PHPStorm from [Jetbrains](https://jetbrains.com) you find an instruction [here](../../../dev_tools/index.md#debugging-drupal-code).
 
 ### Watch the logs
 

docs/dev_tools/index.md

 ---
-title: Development Tools
+title: Developer Tools
 tags:
 - documentation
 - tools
----
+---
\ No newline at end of file
+# Developer Tools
+
+## IDE
+
+We use the IDE's IntelliJ and PHPStorm from [Jetbrains](https://jetbrains.com), because we are convinced to use best toolset in the 
+market so far.
+
+## Debugging Drupal Code
+
+### Add a PHP Server
+
+First, you have to set up a Drupal environment with the tool [l3d](../docker/l3d/index.md). The tool is 
+based on Docker containers.
+
+Now navigate to File->Settings in your IDE and create a server:
+
+![Screenshot](/files/screenshots/settings_php_new_server.png)
+
+Set the following values:
+
+![Screenshot](/files/screenshots/settings_php_add_server.png)
+
+**Important: Always use Docker as name of your server.** 
+
+Do not forget to add the file mapping to `/var/www/html`.
+
+### Add a new Run/Debug Configuration
+
+![Screenshot](/files/screenshots/configuration_add.png)
+
+First create a new `PHP Web Page` configuration:
+
+![Screenshot](/files/screenshots/configuration_new_webpage.png)
+
+Set the following values:
+
+![Screenshot](/files/screenshots/configuration_done.png)
+
+Select the server you just have created.
+
+**Important: Always use Docker as name of your configuration.** 
+
+### Start Debugging
+
+First, check the debug settings in your IDE. It should look something like this:
+
+![Screenshot](/files/screenshots/settings_php_debug.png)
+
+Now activate the `Phone` icon in your IDE:
+
+![Screenshot](/files/screenshots/start_debug.png)
+
+Now you can set your breakpoints and enjoy debugging Drupal code.
+
+## Execute Drupal tests within your IDE
+
+