normalize_query syntax problems (lisibility)

[legrandlegrand]

Each exemple can be verified with pgssp_normalize_query() function.

1. minus sign "-" is removed more than expected:
   select +1.1, -2, 2-1, b-a, b-1
   SELECT +?, ?, ?-?, ba, b?

2. parenthesis "(" ")" are removed more than expected:
   insert into a values (null)
   INSERT INTO a VALUES ?
   or
   select f(1)
   SELECT f?

3. Blank is missing:
   select a from t where b=2 order by c
   SELECT a FROM t WHERE b=?ORDER BY c

4. non quoted identifiers are case sensitive (they should be lowercase):
   select aB,AB,ab,Ab,"xYz","Xyz" from t
   SELECT aB,AB,ab,Ab,"xYz","Xyz" FROM t

5. variables from replaced literals should be typed:
   select 1, 1.1, 'aa'
   SELECT ?, ?, ?
   (this opens others questions about NULL consideration ...)

6. following functions are not common litterals, they should not by replaced:
   select CURRENT_DATE, CURRENT_TIME, LOCALTIME, LOCALTIMESTAMP
   SELECT ?, ?, ?, ?