Add rate limiting example

examples/rate_limiting.rs

@@ -0,0 +1,27 @@
+use listenbrainz::raw::Client;
+
+fn main() {
+    let token = std::env::args().nth(1).expect("No token provided");
+
+    let client = Client::new();
+
+    loop {
+        match client.validate_token(&token) {
+            Ok(response) => {
+                println!("{:?}", response.rate_limit);
+
+                if let Some(remaining) = response.rate_limit.map(|r| r.remaining) {
+                    if remaining == 0 {
+                        break;
+                    }
+                } else {
+                    break;
+                }
+            }
+            Err(err) => {
+                eprintln!("{}", err);
+                break;
+            }
+        }
+    }
+}