Changes from Jonathan Riehl to allow his pgen extension (PEP 269) to work. This includes some more code that used to be part of pgen in the main parser; I'm okay with that. I'll see if the Windows build needs work next.

--- a/Parser/pgen.c	Thu Apr 17 13:13:55 2003 +0000
+++ b/Parser/pgen.c	Thu Apr 17 14:55:42 2003 +0000
@@ -669,6 +669,11 @@
 	return g;
 }
 
+grammar *
+Py_pgen(node *n)
+{
+  return pgen(n);
+}
 
 /*