message: Add stream delete method
diff: @@ -572,7 +572,7 @@ impl Manager {
  self.request(&subject, b"")
  }
  - /// Query stream information.
  + /// Purge stream messages.
  pub fn purge_stream<S: AsRef<str>>(&self, stream: S) -> io::Result<()> {
  let stream: &str = stream.as_ref();
  if stream.is_empty() {
  @@ -585,6 +585,19 @@ impl Manager {
  self.request(&subject, b"")
  }
  + /// Delete stream.
  + pub fn delete_stream<S: AsRef<str>>(&self, stream: S) -> io::Result<()> {
  + let stream: &str = stream.as_ref();
  + if stream.is_empty() {
  + return Err(Error::new(
  + ErrorKind::InvalidData,
  + "the stream name must not be empty",
  + ));
  + }
  + let subject = format!("$JS.API.STREAM.DELETE.{}", stream);
  + self.request(&subject, b"")
  + }
  +
  /// Query stream information.
  pub fn consumer_info<S1, S2>(
  &self,
  