Rename Vool to Sol

Simple is really the descriptive name for the layer
Sure, it is "virtual" but that is not as important as the fact that it is simple (or simplified)
Also objct (based really) is better, since orientated implies it is a little like that, but only orientated, not really it. Sol only has objects, nothing else
Just cause i was renaming anyway

test/sol/send/test_not_found.rb

@@ -0,0 +1,28 @@
+require_relative "../helper"
+
+module Sol
+  class TestSendCachedSimpleSlotMachine < MiniTest::Test
+    include SolCompile
+
+    def setup
+      @compiler = compile_main( "5.div8")
+      @ins = @compiler.slot_instructions.next
+    end
+    def test_check_type
+      assert_equal NotSameCheck , @ins.class , @ins
+    end
+    def test_check_resolve_call
+      assert_equal ResolveMethod , @ins.next(2).class , @ins
+    end
+    def test_dynamic_call_last
+      assert_equal DynamicCall ,  @ins.next(6).class , @ins
+    end
+
+    def test_array
+      check_array [NotSameCheck, SlotLoad, ResolveMethod, Label, MessageSetup ,
+                    ArgumentTransfer, DynamicCall, SlotLoad, ReturnJump,
+                    Label, ReturnSequence, Label]  , @ins
+    end
+
+  end
+end