rename register to risc

seems to fit the layer much better as we really have a very reduced
instruction set

test/risc/test_compat.rb

@@ -0,0 +1,22 @@
+require_relative "../helper"
+
+
+class TestCompat < MiniTest::Test
+
+  def setup
+    Risc.machine.boot unless Risc.machine.booted
+  end
+
+  def test_list_create_from_array
+    array = [1,2,3]
+    list = Parfait.new_list(array)
+    assert_equal array , list.to_a
+  end
+
+  def test_word_create_from_string
+    string = "something"
+    word = Parfait.new_word(string)
+    assert_equal word , Parfait.new_word(string)
+    assert_equal string , word.to_string
+  end
+end