Added domain model to requirements.md

docs/requirements.md

@@ -48,10 +48,6 @@
 
 ### Domain model
 
-To better understand the context of the software system, it is very useful to have a simple UML class diagram with all the key concepts (names, attributes) and relationships involved of the problem domain addressed by your module. 
-Also provide a short textual description of each class. 
-
-Example:
  <p align="center" justify="center">
-  <img src="https://github.com/LEIC-ES-2021-22/templates/blob/main/images/DomainModel.png"/>
+  <img src="../images/DomainModel.png"/>
 </p>