Add class support with constructors, fields, and methods

projects/classes.j

@@ -0,0 +1,11 @@
+class Dog:
+    fn init(self, name):
+        self.name = name
+
+    fn bark(self):
+        println("guau!")
+
+d = Dog("ahi te va")
+x = d.bark()
+println("Hola ", d.name)
+debugHeap()