Master account sequence management pvy

instead of doing a read then several browse it is more efficient to first execute the loop on the fy:

for fy in self.pool.get('account.fiscalyear').browse(...):

then perform a browse on the current object and just use the .fields notation to go down a level, the orm will cache everything and it will be faster than executing several browse.

as example: 
for obj in self.browse(cr, uid, ids, context):
 if obj.journal_ids:
  for journal in obj.journal_ids
   sequences = journal.refund_sequence ...