ora.Time should be nullable but is not

[sosdarko]

Hi, when executing:

	l := &ora.Time{}
	stm, err := ses.Prep(`begin :1 := null; end;`)
	_, err = stm.Exe(l)
	fmt.Println("Result - ", l.IsNull, l.Value)

l.IsNull is false but should be true?

I have installed gopkg.in/rana/ora.v4 on 64bit windows.