[IMP] point_of_sale: distinguish discounted lines

After closing a POS session, the pos order lines are grouped by product.
Instead, distinguish products with a different discount notice to have different lines for such products in the generated account.move for better traceability.
[FIX] fix a crash with create popup forms (web client)

it was trying to call the forme 'hide' method on the searchview.  To
solve the problem, I readded the method (and renamed it to do_hide for
consistency with views)
[IMP] crm: business model cleaning

Models renamings:
- crm.case.stage becomes crm.stage
- crm.case.section becomes crm.team

Model split:
crm.case.categ has been splitted into:
- crm.phonecall.tag
- crm.lead tag
- crm.claim.tag
- crm.helpdesk.tag

Models removal:
- crm.payment.mode
- crm.segmentation
- report.crm.case

Removal of the crm_profiling module

(all these refactorings have been done in order to ease new API
migrations)
[IMP] added oldname key to fields which are renamed.
[FIX] oldname does not work on many2many