Builtin is no more, final conversions done

All preloading where it needs to be
(some)tests for the preload
split compiler test
remembered binary tests (usually just run on travis)

lib/rubyx/interpret.rb

@@ -24,8 +24,10 @@ class RubyXC < Thor
     rescue
       fail MalformattedArgumentError , "No such file #{file}"
     end
+    code = get_preload + ruby
+
     compiler = RubyX::RubyXCompiler.new(extract_options)
-    linker = compiler.ruby_to_binary(ruby, :interpreter)
+    linker = compiler.ruby_to_binary(code, :interpreter)
 
     puts "interpreting #{file}"