code: public StrBuilder appendAll(final Iterator<?> it) {
          if (it != null) {
              while (it.hasNext()) {
                  append(it.next());
              }
          }
          return this;
      }
docs: Appends each item in an iterator to the builder without any separators.
  Appending a null iterator will have no effect.
  Each object is appended using {@link #append(Object)}.
  
  @param it  the iterator to append
  @return this, to enable chaining
  @since 2.3