Found bug

[yurilavinas]

A bug was found when calling the summary function from the summary.moead.R when giving the ref.points as parameters. The var "Y" is not defined alone in any context, but its in the "object" variable.

In that file, the assertthat:: function should be updated to

assertthat::is.count(ndigits), nullRP || is.numeric(ref.point), nullRP || length(ref.point) == ncol(object$Y), nullRF || is.numeric(ref.front), nullRF || ncol(ref.front) == ncol(object$Y))