Error handling for correlations and plotting correlations

[nikosbosse]

The function should give you an intuitive error message, when you try to pass the output form "summarise_scores" directly into "plot_correlations".

correlation should give a warning when it filters out columns because not all values are numeric or finite here:

  # remove all non metrics and non-numeric columns
  df <- scores[, .SD, .SDcols = sapply(
    scores,
    function(x) {
      (all(is.numeric(x))) && all(is.finite(x))
    }
  )]