Fixed issue Mindcraft-59.
Refactored the way PerForm step shows actions in the different columns.
Improved action filtering in client-side: actions with uncompleted to do datetime are displayed only if action is not done or if it is done today.
Improved getActions method in server-side: actions are shown if to do datetime is defined with timeframe and it is to do yesterday, today or tomorrow, or in case to do datetime is partial or not defined, actions are shown if date_todo is empty or today and if date_done is empty or today.