[IMP] Manufacturing : Improved some usability issues.

Task : https://www.odoo.com/web#id=10541&view_type=form&model=project.task&menu_id=3942&action=327
pad link : https://pad.odoo.com/p/r.fZCshEnjNImVXxFn
Consumed product tab : Quantity under "Products to Consume" and "Consumed Products" are not aligned, the "Products to Consume" displayed "Products to Consume" slightly upper than "Consumed Product", you can see following image,
![display_issue](https://cloud.githubusercontent.com/assets/7599774/5389391/8f59d11c-8121-11e4-9f92-61024c90e8c4.png)