code: public static boolean[] add(final boolean[] a, final boolean element) {
          if (N.isNullOrEmpty(a)) {
              return Array.of(element);
          }
  
          final boolean[] newArray = new boolean[a.length + 1];
  
          copy(a, 0, newArray, 0, a.length);
          newArray[a.length] = element;
  
          return newArray;
      }
docs: <p>
  Copies the given array and adds the given element at the end of the new
  array.
  
  @param a
  @param element
  @return A new array containing the existing elements plus the new element