seperate different Position classes into own files

also tests
and have Position module keep all positions
(singletons should be at module, not class level)

test/risc/position/test_code_position.rb

@@ -0,0 +1,26 @@
+require_relative "../helper"
+
+module Risc
+  # tests that require a boot and test propagation
+  class TestPositionBasic < MiniTest::Test
+    def setup
+      Risc.machine.boot
+      @binary = Parfait::BinaryCode.new(1)
+      @label = Label.new("hi","ho")
+    end
+    def test_set_bin
+      pos = Position.set( @binary , 0 , Parfait.object_space.get_main)
+      assert_equal Position::CodePosition , pos.class
+    end
+    def test_bin_propagates_existing
+      @binary.extend_to(16)
+      Position.set( @binary , 0 , Parfait.object_space.get_main)
+      assert_equal @binary.padded_length , Position.get(@binary.next).at
+    end
+    def test_bin_propagates_after
+      Position.set( @binary , 0 , Parfait.object_space.get_main)
+      @binary.extend_to(16)
+      assert_equal @binary.padded_length , Position.get(@binary.next).at
+    end
+  end
+end