Redesign Review Picking Slip Page

1. Delete function to show most recent picking slips.
2. Add select options to the page, Year and Month are mandatory.
3. Use seprate Ajax call to get picking slip data and move lines in each picking slip.
Add controller functions to review packing slip page

1. get picking data and line data seprately.
2. modify fields in returned data.
Adjust format
Add audit state to stock.picking

1. Add audit state field to stock.picking.
2. Add function to change audit state in stock.picking when products are audited.
3. Move flag audit function from stock_picking to stock_move. Rewrite function using openerp ORM method instead of SQL query.
4. Allow 0 product's quantity when performing audit.