several larger changes came together, bit of cleaning too

- all code must be in functions (which must be in classes).
— changes a fair few tests
— also changes api, as method is not recursive, not passed around
- all state in instance vars in compiler (no accessors)
- class is another such variable, surely more coming
all green again

test/fragments/test_hello.rb

@@ -5,7 +5,11 @@ class TestHello < MiniTest::Test
 
   def test_hello
     @string_input = <<HERE
-"Hello Raisa, I am salama".putstring()
+class Object
+  int main()
+    "Hello Raisa, I am salama".putstring()
+  end
+end
 HERE
     @expect = []
     check