rename function_call to call_site in all levels to avoid confusion

lib/vm/call_site.rb

@@ -0,0 +1,25 @@
+module Vm
+
+  # name and args , return
+
+  class CallSite < Value
+
+    def initialize(name , args , function )
+      @name = name
+      @args = args
+      @function = function
+    end
+    attr_reader  :function , :args , :name
+    
+    def load_args into
+      args.each_with_index do |arg , index|
+        puts "load " + arg.inspect
+        arg.load( into , index )
+      end
+    end
+
+    def do_call into
+      into.add_code CMachine.instance.function_call into , self
+    end
+  end
+end