#1113 Link uml-reverse-mapper created class diagrams to readme, where needed

caching/README.md

@@ -15,6 +15,7 @@ To avoid expensive re-acquisition of resources by not releasing
 the resources immediately after their use. The resources retain their identity, are kept in some
 fast-access storage, and are re-used to avoid having to acquire them again.
 
+## Class diagram
 ![alt text](./etc/caching.png "Caching")
 
 ## Applicability