* Fix a bug about sizeof() at idx_fake_oid of info.
* Return 0 for the column size when the size of numeric items are unknown.
Also improve the calculation of scale of numeric items when it is not
explicitly specified.
* Change to use 'if' instead of an inappropriate 'else if' at cursor of convert.
* Remember to set permanent flag to holdable cursors on commit with no
precedent rollback (to savepoint) operations.
This fixes a crash bug in case of cursor operations across transaction.
* Fix a bug about the handling of the SQL_RETRIEVE_DATA option.
* Fix cursor bug introduced by the previous change.
* Move the setting of folder name of libpq or gssapi related dlls from .wxs
file to .bat file.
* Fix a bug which returns incorrect values for SQL_DATETIME_SUB.
