Separate parse-analysis for utility commands out of parser/analyze.c

(which now deals only in optimizable statements), and put that code
into a new file parser/parse_utilcmd.c.  This helps clarify and enforce
the design rule that utility statements shouldn't be processed during
the regular parse analysis phase; all interpretation of their meaning
should happen after they are given to ProcessUtility to execute.
(We need this because we don't retain any locks for a utility statement
that's in a plan cache, nor have any way to detect that it's stale.)

We are also able to simplify the API for parse_analyze() and related
routines, because they will now always return exactly one Query structure.

In passing, fix bug #3403 concerning trying to add a serial column to
an existing temp table (this is largely Heikki's work, but we needed
all that restructuring to make it safe).

src/backend/rewrite/rewriteDefine.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/rewrite/rewriteDefine.c,v 1.120 2007/04/27 22:05:48 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/rewrite/rewriteDefine.c,v 1.121 2007/06/23 22:12:51 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -20,8 +20,8 @@
 #include "catalog/pg_rewrite.h"
 #include "miscadmin.h"
 #include "optimizer/clauses.h"
-#include "parser/analyze.h"
 #include "parser/parse_expr.h"
+#include "parser/parse_utilcmd.h"
 #include "rewrite/rewriteDefine.h"
 #include "rewrite/rewriteManip.h"
 #include "rewrite/rewriteSupport.h"
@@ -191,7 +191,7 @@ DefineRule(RuleStmt *stmt, const char *queryString)
 	Node	   *whereClause;
 
 	/* Parse analysis ... */
-	analyzeRuleStmt(stmt, queryString, &actions, &whereClause);
+	transformRuleStmt(stmt, queryString, &actions, &whereClause);
 
 	/* ... and execution */
 	DefineQueryRewrite(stmt->rulename,