CLOSED - task 15: Design where the Intereses should be 
https://github.com/lomagno2003/inmobiliarias.rest/issues/issue/15
CLOSED - task 14: Implement unit tests for the Balance resource 
https://github.com/lomagno2003/inmobiliarias.rest/issues/issue/14
CLOSED - task 17: Refactor the ProcentajeDeGastos on UnidadFuncional to
contemplate changes over the time 
https://github.com/lomagno2003/inmobiliarias.rest/issues/issue/17
OPEN - task 18: Refactor the Extract method on BalanceCalculatorLoadAll 
https://github.com/lomagno2003/inmobiliarias.rest/issues/issue/18