15 more chain saw manuals added

15 more chain saw manuals and parts lists have been added recently:

- Craftsman: 1 chain saw manual
- Hitachi: 1 chain saw manual, 1 chain saw parts list
- Homelite: 3 chain saw parts lists
- McCulloch: 3 chain saw parts lists
- Stihl: 3 chain saw manuals, 1 chain saw parts list
- Tanaka: 1 chain saw manual, 1 chain saw parts list