add some documentation structure

docs/concepts-and-configurations/documentation-structure.md

@@ -0,0 +1,16 @@
+---
+title: Documentation Structure
+order: 1
+summary: >-
+  How our documentation is organized and what we do to balance ease of writing and understanding.
+---
+
+!!! info "ToDo"
+
+    This section needs updating
+
+- Docs should be english
+- Guides are for step-by-step things
+  - Guides always have a "Goal" explicitly formulated
+- Concepts and Configuration aim to make readers understand something in detail
+