Chages in transactions process

- Using ced number instead of the SAR code
- Not using any more the store in save process, now only the company is
required.
- When adding multiple transactions from file verification made to avoid
inconsistency problems in db. Now all are being added and at the end a
one single savechanges is called. Also added a way to rollback if
needed.
- Ui changes needed to delete stores and to add company in transactions
ui