pgsql-server: This patch implement the TODO [ALTER DATABASE foo OWNER TO

Log Message:
-----------
This patch implement the TODO [ALTER DATABASE foo OWNER TO bar].
It was necessary to touch in grammar and create a new node to make home
to the new syntax. The command is also supported in E
CPG. Doc updates are attached too. Only superusers can change the owner
of the database. New owners don't need any aditional
privileges.

Euler Taveira de Oliveira

Modified Files:
--------------
    pgsql-server/doc/src/sgml/ref:
        alter_database.sgml (r1.11 -> r1.12)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/doc/src/sgml/ref/alter_database.sgml.diff?r1=1.11&r2=1.12)
    pgsql-server/src/backend/commands:
        dbcommands.c (r1.133 -> r1.134)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/commands/dbcommands.c.diff?r1=1.133&r2=1.134)
    pgsql-server/src/backend/nodes:
        copyfuncs.c (r1.282 -> r1.283)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/nodes/copyfuncs.c.diff?r1=1.282&r2=1.283)
        equalfuncs.c (r1.221 -> r1.222)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/nodes/equalfuncs.c.diff?r1=1.221&r2=1.222)
    pgsql-server/src/backend/parser:
        gram.y (r2.455 -> r2.456)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/parser/gram.y.diff?r1=2.455&r2=2.456)
    pgsql-server/src/backend/tcop:
        utility.c (r1.216 -> r1.217)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/backend/tcop/utility.c.diff?r1=1.216&r2=1.217)
    pgsql-server/src/bin/psql:
        tab-complete.c (r1.106 -> r1.107)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/bin/psql/tab-complete.c.diff?r1=1.106&r2=1.107)
    pgsql-server/src/include/commands:
        dbcommands.h (r1.30 -> r1.31)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/include/commands/dbcommands.h.diff?r1=1.30&r2=1.31)
    pgsql-server/src/include/nodes:
        nodes.h (r1.155 -> r1.156)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/include/nodes/nodes.h.diff?r1=1.155&r2=1.156)
        parsenodes.h (r1.255 -> r1.256)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/include/nodes/parsenodes.h.diff?r1=1.255&r2=1.256)
    pgsql-server/src/interfaces/ecpg/preproc:
        preproc.y (r1.283 -> r1.284)

(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/interfaces/ecpg/preproc/preproc.y.diff?r1=1.283&r2=1.284)