Add tasks for all the new languages

Task/Enforced-immutability/Oforth/enforced-immutability.oforth

@@ -0,0 +1,12 @@
+Object Class new: MyClass(a, b)
+
+MyClass method: setA(value)  value := a ;
+MyClass method: setB(value)  value := b ;
+
+MyClass method: initialize(v, w)  self setA(v) self setB(w) ;
+
+MyClass new(1, 2)                // OK : An immutable object
+MyClass new(1, 2) setA(4)        // KO : An immutable object can't be updated after initialization
+MyClass new(ListBuffer new, 12)  // KO : Not an immutable value.
+ListBuffer new Constant new: T   // KO : A constant cannot be mutable.
+Channel new send(ListBuffer new) // KO : A mutable object can't be sent into a channel.