[video_player_avplay] Add setStreamingProperty API

[xiaowei-guan]

Add setStreamingProperty API:

  /// Sets specific feature values for HTTP, MMS, or specific streaming engine (Smooth Streaming, HLS, DASH, DivX Plus Streaming, or Widevine).
  /// The available streaming properties depend on the streaming protocol or engine.
  /// Use the CUSTOM_MESSAGE property for streaming engine or CP-specific settings.
  Future<void> setStreamingProperty(StreamingPropertyType type, String value) ;

Native interface:

/**
   * @brief     Set streamingengine property
   * @param     [in] type : attribute type. \n
   *             type can be \n
   *               "COOKIE" \n
   *               "USER_AGENT" \n
   *               "RESUME_TIME" \n
   *               "ADAPTIVE_INFO"
   * @param     [in] value : value of attribute type
   * @pre       The player state can be all of #State except #State::kNone
   */
  virtual void SetStreamingProperty(const std::string& type,
                                    const std::string& value)