Function crypto_crawler::crawl_ticker

pub fn crawl_ticker(
    exchange: &str, 
    market_type: MarketType, 
    symbols: Option<&[String]>, 
    on_msg: Arc<Mutex<dyn FnMut(Message) + Send + 'static>>, 
    duration: Option<u64>
)

Crawl 24hr rolling window ticker.

If symbols is None, it means all trading symbols in the market_type, and updates the latest symbols every hour.