Updated test cases documentation

docs/test_cases/t00037.md

@@ -0,0 +1,50 @@
+# t00037 - Anonymous nested struct test case
+## Config
+```yaml
+compilation_database_dir: ..
+output_directory: puml
+diagrams:
+  t00037_class:
+    type: class
+    generate_packages: true
+    glob:
+      - ../../tests/t00037/t00037.cc
+    using_namespace:
+      - clanguml::t00037
+    include:
+      namespaces:
+        - clanguml::t00037
+```
+## Source code
+File t00037.cc
+```cpp
+namespace clanguml {
+namespace t00037 {
+
+struct ST {
+    struct {
+        double t;
+        double x;
+        double y;
+        double z;
+    } dimensions;
+};
+
+struct A {
+    A()
+    {
+        st.dimensions.t = -1;
+        st.dimensions.x = 1;
+        st.dimensions.y = 1;
+        st.dimensions.z = 1;
+    }
+
+    ST st;
+};
+
+} // namespace t00037
+} // namespace clanguml
+
+```
+## Generated UML diagrams
+![t00037_class](./t00037_class.svg "Anonymous nested struct test case")