#6. Starting to implement new design inspired by ZenMoney
#6. Some formatting
#6. Flash messages view
#6. Balance block UI
#5. Setting default sorting on Transactions relationship
#6. Last transactions widget
#5. Changing default order to scope as preferred in Rails 4
#5. Handling Transactions without Category
#7. Adding Currency model
#7. Adding ExchangeRate model + tasks for getting rates
#7. Rake task for ExchangeRate downloading is ready