Make classes know their name.

test/class/name.wren

@@ -0,0 +1,9 @@
+class Foo {}
+
+IO.print(Foo.name) // expect: Foo
+IO.print(Foo.type.name) // expect: Foo metaclass
+
+// Make sure the built-in classes have proper names too.
+IO.print(Object.name) // expect: Object
+IO.print(Class.name) // expect: Class
+IO.print(Bool.name) // expect: Bool