Negative Order Total Amount on the Bill edit form

Bill edit form:

• Amount:
  • Order can be saved with Negative item Amount on “Item and Expense tabs;
  • the logic isn’t changed;
• Save Draft / Save & Approve buttons:
  • if the Order was created with Negative Order Total Amount:
    • after clicking on the button -> the OMS message is displayed:
      • Text: “Sorry, you can not save Bill with negative total.”
      • “OK” button:
        • after clicking on the button 
          • the message is closed;
          •  the Bill edit form is displayed.