pgsql: Update wording: * Allow a database in tablespace t1 with tables

Log Message:
-----------
Update wording:

* Allow a database in tablespace t1 with tables created in tablespace t2
to be used as a template for a new database created with default
tablespace t2

All objects in the default database tablespace must have default tablespace
specifications. This is because new databases are created by copying
directories. If you mix default tablespace tables and tablespace-specified
tables in the same directory, creating a new database from such a mixed
directory would create a new database with tables that had incorrect
explicit tablespaces. To fix this would require modifying pg_class in the
newly copied database, which we don't currently do.

Modified Files:
--------------
pgsql/doc:
TODO (r1.1365 -> r1.1366)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/TODO.diff?r1=1.1365&r2=1.1366)