+#' Flat prediction: always forecast a serie of zeros.
+#' This serie is then adjusted using the ".pjump" function (see \code{Forecaster} class).
+#'
+#' @usage # ZeroForecaster$new(pjump)
+#'
+#' @docType class
+#' @format R6 class, inherits Forecaster
+#' @aliases F_Zero