Nested OLs do not start with the number of their parent but instead, start counting completely anew.

Offer a solution allowing nested OLs to generate this form of rendering.

1.   title1

1.1   subtile11

1.2   subtile12

2.   title2

2.1   subtile21

2.2   subtile22

2.2.1   subtile221

2.2.2   subtile222

2.3   subtile23

3.   title3