Improve documentation in README

Description

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

README.md

@@ -159,11 +159,9 @@ Firstly, make sure that you're located in the root directory of goSDN.
 `goSDN` provides a `Makefile` for all common use cases.
 
 ```sh
-# build the application files for goSDN, cSBI orchestrator, gosdnc (CLI).
-make build
+# build the application files for goSDN, cSBI orchestrator (currently not in use), gosdnc (CLI).
 
-# build the Dockerfiles for goSDN, cSBI orchestrator, gosdnc (CLI).
-make containerize-all
+make build
 ```
 
 Depending on how you want to use the controller, you might need to edit the example config files and provide the path to this or a new config file.
@@ -188,6 +186,14 @@ If you want to use the [playground](#playground) you have to make sure you
 have [containerlab](https://containerlab.dev/install/) installed on your
 system.
 
+It is possible to build all the docker containers using the following command from the root directory of the project:
+```sh
+# build the Docker containers for goSDN, cSBI orchestrator (currently not in use), gosdnc (CLI) as well as some of the provided example applications.
+make containerize-all
+```
+
+Note that this command is included as a step when using any of the following enviroments like the playgrounds, labs etc. and therefore can be skipped.
+
 ### Playground
 
 With the help of [containerlab](https://containerlab.dev/) we provide simple test environments to play around with.