SlotLanguage reborn in the Machine

Just added the compiler, that can parse Slot directly into SlotMachine code (no language layer in between)
Still unclear wheather the Maker is a thing, but since it was in the Language layer i did not remove it (yet)
Otherwise just the compiler and all the tests, moved from the slot_language.

test/slot_machine/compiler/test_slot_compiler.rb

@@ -0,0 +1,17 @@
+require_relative "../helper"
+
+module SlotMachine
+  class TestSlotCompiler < MiniTest::Test
+    include SlotHelper
+
+    def test_init
+      assert SlotCompiler.new
+    end
+    def test_labels
+      assert SlotCompiler.new.labels.empty?
+    end
+    def test_basic_compile
+      assert_equal SlottedMessage , compile("a").class
+    end
+  end
+end