[IMP] point-of-sale, customer selection, remove dead code

addons/hw_escpos/escpos/escpos.py

addons/point_of_sale/__openerp__.py

addons/point_of_sale/controllers/main.py

addons/point_of_sale/point_of_sale.py

addons/point_of_sale/point_of_sale_view.xml

addons/point_of_sale/static/src/css/pos.css

addons/point_of_sale/static/src/img/logo.png

addons/point_of_sale/static/src/js/db.js

addons/point_of_sale/static/src/js/devices.js

addons/point_of_sale/static/src/js/models.js

addons/point_of_sale/static/src/js/screens.js

addons/point_of_sale/static/src/js/widgets.js

addons/point_of_sale/static/src/xml/pos.xml

addons/point_of_sale/views/templates.xml