cloid request

[simsim-14]

Could you please change the cloid type to be "String"? It is kind of restraining to have the type of the order id to exclusively be of uuid::Uuid type, because people may want to append some identifiers to the order_id except from the random identifier.

[simsim-14]

Here:

pub struct ClientOrderRequest {
    pub asset: String,
    pub is_buy: bool,
    pub reduce_only: bool,
    pub limit_px: f64,
    pub sz: f64,
    pub cloid: Option<Uuid>, <----- 
    pub order_type: ClientOrder,
}

Also for MarketCloseParams and MarketOrderParams.