Fix Financial app: Add correctly a new transaction in the results

- When add a new transaction, use it as AccountTransactionView instead AccountTransaction.
Attributes used to mark transactions as bold, are found only on the view.
- Update validatecoverage
Decrease expected coverage on stoqlib/database/orm.py - sync() is no longer tested

Change-Id: I43638f4d2a1011265a52bdcf16f73177f9e657af