15 more chain saw manuals added

15 more chain saw and pole saw manuals and parts lists were added recently:

- Earthwise: 1 chain saw manual
- Husqvarna: 1 chain saw parts list
- McCulloch: 2 chain saw parts lists
- Partner: 1 chain saw parts list
- Poulan: 6 chain saw parts lists, 2 pole saw parts lists
- Poulan Pro: 2 chain saw parts lists