D = redate(D,OldDate,NewDate)
D [ struct ] - Input database with tseries objects.
OldDate [ numeric ] - Base date that will be converted to a new date in all tseries objects.
NewDate [ numeric ] - A new date to which the base date OldDate will be changed in all tseries objects; newDate need not be the same frequency as OldDate.
d [ struct ] - Output database where all tseries objects have identical data as in the input database, but with their time dimension changed.