title: DataGridView Readonly "bug"
body: <p>I have a <code>datagridview</code> to display some data. Some rows between data are <code>separator rows</code> so those are <code>readonly</code>. In some cases the whole <code>datagridview</code> might be <code>readonly</code>. But when I switch it back to <code>readonly = false</code>, all the rows are editable. Is it possible with out having to set again the <code>readonly</code> property of each row manually that my row came back as they were before?</p>