Added test case for accessing comments from inja templates

tests/t00050/.clang-uml

@@ -0,0 +1,38 @@
+compilation_database_dir: ..
+output_directory: puml
+diagrams:
+  t00050_class:
+    type: class
+    glob:
+      - ../../tests/t00050/t00050.cc
+    include:
+      namespaces:
+        - clanguml::t00050
+    using_namespace: clanguml::t00050
+    plantuml:
+      after:
+        - >
+           note left of {{ alias("A") }}
+              {{ comment("A") }}
+           end note
+
+        - >
+          {% for element in diagram.elements %}
+          {% if element.type == "class" and existsIn(element, "comment")  %}
+          
+          note top of {{ element.alias }}
+             {{ element.comment }}
+          end note
+          
+          {% endif %}
+          {% endfor %}
+        - >
+          {% for element in diagram.elements %}
+          {% if element.type == "enum" and existsIn(element, "comment") %}
+          
+          note bottom of {{ element.alias }}
+             {{ element.comment }}
+          end note
+          
+          {% endif %}
+          {% endfor %}