fix Issue 2495 - const syntax for member functions needs better descr…

…iption

class.dd

@@ -206,6 +206,24 @@ void test(Foo foo) {
         can be accessed.
         )
 
+$(V2
+	$(P Non-static member functions can have, in addition to the usual
+	$(GLINK2 declaration, FunctionAttribute)s, the attributes
+	$(D const), $(D immutable), $(D shared), or $(D inout).
+	These attributes apply to the hidden $(I this) parameter.
+	)
+---
+class C {
+  int a;
+  const void foo() {
+    a = 3; // error, 'this' is const
+  }
+  void foo() immutable {
+    a = 3; // error, 'this' is immutable
+  }
+---
+)
+
 <h3>$(LNAME2 synchronized-functions, Synchronized Functions)</h3>
 
         $(P Synchronized class member functions have the storage class
@@ -1170,7 +1188,7 @@ new ($(I ArgumentList)) $(I Identifier) ($(I ArgumentList));
         )
 
 $(V2
-$(SECTION3 <a name="ConstClass">Const, Immutable and Shared Classes</a>,
+$(SECTION3 <a name="ConstClass">Const Immutable and Shared Classes</a>,
         $(P If a $(I ClassDeclaration) has a $(CODE const), $(CODE immutable)
         or $(CODE shared) storage class, then it is as if each member of the class
         was declared with that storage class.