keep_default=False fails when default value provided is empty string or 0

[cmkmrr]

When using add_column's keep_default parameter, if the default provided in the migration is empty string it is never removed.

In svn rev260 south/db/generic.py(211) the check for keep_default is:

if not keep_default and field.default:

When I think the correct check should be:

if not keep_default and field.default is not None:

[andrew]

Agreed. Fixed in [261].