cmon clippy, it's not worth making a new type

src/main.rs

@@ -1,5 +1,3 @@
-#![feature(in_band_lifetimes)]
-#![feature(async_closure)]
 use serenity::client::Client;
 use serenity::framework::standard::StandardFramework;
 use serenity::futures::lock::Mutex;

src/track.rs

@@ -29,6 +29,7 @@ impl TypeMapKey for InfoSent {
 
 pub struct Sent;
 
+#[allow(clippy::type_complexity)]
 impl TypeMapKey for Sent {
    type Value = Arc<Mutex<HashMap<(ChannelId, MessageId), (ChannelId, MessageId)>>>;
 }