Get object in post. Also, removed print statements
Created balances model for double-entry bookkeeping; get_credit core function; OrderProductCollection model to save corrections (refunds)
Removed obsolete imports
Create debit object and link to it from order when placing order
Fixed circular import. blank=True on Order.debit
get_debit (reverses get_credit)
Created BalanceManager, default related manager for Balance, so credit/debit can be accessed from templates.
typofix
Added basic Payment model.
Moved finance related models to new 'finance' app
Added user to payment