ALTER EXTENSION UPGRADE, v3

Hi,

PFA version 3 of the ALTER EXTENSION PATCH, cleaned and merged against
recent HEAD and extension's branch from which I just produced the v30
patch.

It includes a way to upgrade "from null", that is from pre-9.1, and the
specific upgrade files to achieve that for all contribs.  That goes like
this:

dim=# \i ~/pgsql/exts/share/contrib/lo.sql
CREATE DOMAIN
CREATE FUNCTION
CREATE FUNCTION
dim=# create wrapper extension lo;
CREATE EXTENSION
dim=# alter extension lo upgrade;
ALTER EXTENSION
dim=# alter extension lo set schema utils;
ALTER EXTENSION
dim=# \dx lo
    Objects in extension "lo"
       Object Description        
---------------------------------
 function utils.lo_manage()
 function utils.lo_oid(utils.lo)
 type utils.lo
(3 rows)

Regards,
-- 
Dimitri Fontaine
http://2ndQuadrant.fr     PostgreSQL : Expertise, Formation et Support