clarify linting

Author: Sebastian Gumprich

CONTRIBUTING.md

@@ -1,3 +1,5 @@
+## Local Development and testing
+
 We accept all kinds of contributions, whether they are bug fixes, pull requests or documentation updates!
 
 If you want to develop new content for this collection or improve what is already here, the easiest way to work on the collection is to clone it into one of the configured [`COLLECTIONS_PATH`](https://docs.ansible.com/ansible/latest/reference_appendices/config.html#collections-paths), and work on it there.
@@ -11,3 +13,33 @@ export COLLECTIONS_PATH=$(pwd)/collections:$COLLECTIONS_PATH
 ```
 
 You can find more information in the [developer guide for collections](https://docs.ansible.com/ansible/devel/dev_guide/developing_collections.html#contributing-to-collections), and in the [Ansible Community Guide](https://docs.ansible.com/ansible/latest/community/index.html).
+
+
+### Linting with tox
+
+After making code changes, please run the linters and fix all errors:
+
+```
+> tox -elinters
+```
+
+### Updating the tests and examples
+
+If you add new features or arguments to the existing modules, please add them to the examples in the module itself.
+The integration tests and examples in our documentation are then generated from the module-examples.
+
+To trigger this generation, you need to run the script `hacking/update_examples_and_tests.sh` from the root of the repository. For this you need to have yq in version 3 installed (see https://mikefarah.gitbook.io/yq/v/v3.x/).
+
+### Integration tests with docker
+
+```
+# run icinga in a container and forward port 80
+> docker run -d -p 80:80 schurzi/icinga2
+
+# run ansible-test
+> ansible-test integration
+
+# alternatively run the test playbooks against the container
+> ansible-playbook tests/integration/targets/icinga/normalmode.yml
+> ansible-playbook tests/integration/targets/icinga/checkmode.yml
+```