Add duplicate invoice number error message in sales module

Fix colspan width for receivings (one column was added for
receiving_quantity)

application/controllers/sales.php

@@ -235,7 +235,7 @@ class Sales extends Secure_area
 		{
 			$data['invoice_number']=$invoice_number;
 			//SAVE sale to database
-			$data['sale_id']='POS '.$this->Sale->save($data['cart'], $customer_id,$employee_id,$comment,$data['payments'],$invoice_number);
+			$data['sale_id']='POS '.$this->Sale->save($data['cart'], $customer_id,$employee_id,$comment,$invoice_number,$data['payments']);
 			if ($data['sale_id'] == 'POS -1')
 			{
 				$data['error_message'] = $this->lang->line('sales_transaction_failed');

application/models/sale.php

@@ -40,7 +40,7 @@ class Sale extends CI_Model
 		return $success;
 	}
 	
-	function save ($items,$customer_id,$employee_id,$comment,$payments,$sale_id=false,$invoice_number=NULL)
+	function save ($items,$customer_id,$employee_id,$comment,$invoice_number,$payments,$sale_id=false)
 	{
 		if(count($items)==0)
 			return -1;

application/views/receivings/receiving.php

@@ -76,7 +76,7 @@ if(isset($error))
 if(count($cart)==0)
 {
 ?>
-<tr><td colspan='7'>
+<tr><td colspan='8'>
 <div class='warning_message' style='padding:7px;'><?php echo $this->lang->line('sales_no_items_in_cart'); ?></div>
 </tr></tr>
 <?php