integer was wrong padded§ length

or rather right (2 as should be and will be)
but currently we use next AND value + type means 3, rounded 4
because we can’t swap types at compile time (as is planned at runtime,
we use next OR value)

test/parfait/test_data_object.rb

@@ -0,0 +1,46 @@
+require_relative "helper"
+
+module Parfait
+  class TestClass < ParfaitTest
+
+    def test_data_class_api_base
+      assert_raises {DataObject.type_length}
+    end
+    def test_data_class_api4
+      assert_equal 4 , Data4.memory_size
+    end
+    def test_data_class_api8
+      assert_equal 8 , Data8.memory_size
+    end
+    def test_data_class_api16
+      assert_equal 16 , Data16.memory_size
+    end
+    def test_data_class_api32
+      assert_equal 32 , Data32.memory_size
+    end
+    def test_int_len
+      assert_equal 4 , Integer.new(1).data_length
+    end
+    def test_true_len
+      assert_equal 4 , TrueClass.new.data_length
+    end
+    def test_false_len
+      assert_equal 4 , FalseClass.new.data_length
+    end
+    def test_nil_len
+      assert_equal 4 , NilClass.new.data_length
+    end
+    def test_int_pad
+      assert_equal 16 , Integer.new(2).padded_length
+    end
+    def test_true_pad
+      assert_equal 16 , TrueClass.new.padded_length
+    end
+    def test_false_pad
+      assert_equal 16 , FalseClass.new.padded_length
+    end
+    def test_nil_pad
+      assert_equal 16 , NilClass.new.padded_length
+    end
+  end
+end