code: function safeFormat(value, formatter) {
    if (value == null || isNaN(value)) {
      return value;
    }
  
    return formatter(value);
  }
docs: Returns null/undefined for null/undefined values,
  otherwise it returns the result of a passed in formatter
  
  @param {Any} value value to format
  @param {Function} formatter formatter function
  @return Formatted value or null/undefined
   @module Formatters