code: public HttpHeaders set(CharSequence name, Object value) {
          return set(name.toString(), value);
      }
docs: Sets a header with the specified name and value.
  
  If there is an existing header with the same name, it is removed.
  If the specified value is not a {@link String}, it is converted into a
  {@link String} by {@link Object#toString()}, except for {@link Date}
  and {@link Calendar}, which are formatted to the date format defined in
  <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.3.1">RFC2616</a>.
  
  @param name The name of the header being set
  @param value The value of the header being set
  @return {@code this}