Convert value to Decimal when searching receivabel/payable

issue2299
review191001
(transplanted from e0e172026e4683c47ab6681203912cb9962d906f)

party.py

@@ -176,7 +176,7 @@ class Party(ModelSQL, ModelView):
                 'GROUP BY l.party '
                 'HAVING (SUM((COALESCE(l.debit, 0) - COALESCE(l.credit, 0))) ' \
                         + clause[1] + ' %s)',
-                    [code] + today_value + [company_id] + [clause[2]])
+                    [code] + today_value + [company_id] + [Decimal(clause[2])])
         return [('id', 'in', [x[0] for x in cursor.fetchall()])]
 
 Party()