POS modifications

Numerous modifications of the Point Of Sale :
=============================================

- Customer pannel
- Editing / adding customers / link to sponsor
- Intuitive browsing for customers (right pan) - by letter
- Browse customer sales history : see its sales and all its products
- Cashier pannel at bottom-left
- Custom packs (can contain templates and their variants : on demand)
- POS internal messaging (instant, delayed, recurrent / text or image)
- Special discount : shop manager can allow special discount by entering
a password