#' \code{getTime()} below. Each cell .data[[i]] is itself a list containing five slots,
#' as described in the 'field' section.
#'
+#' @usage data <- Data$new()
+#'
#' @field .data[[i]] List of
#' \itemize{
#' \item time: vector of times
#' \item{\code{getStdHorizon()}}{
#' Number of time steps from serie[1] until midnight}
#' \item{\code{append(time, serie, exo, exo_hat)}}{
-#' Measured data for given vector of times + exogenous predictions from last midgnight.
+#' Measured data for given vector of times + exogenous predictions from
+#' last midgnight.}
#' \item{\code{getTime(index)}}{
#' Times (vector) at specified index.}
#' \item{\code{getCenteredSerie(index)}}{