Run clippy on all targets and all features and fix clippy warning.

.travis.yml

@@ -4,7 +4,7 @@ before_script:
   - "rustup component add clippy"
 script:
   - "cargo fmt --all -- --check"
-  - "cargo clippy -- -D warnings"
+  - "cargo clippy --all-targets --all-features -- -D warnings"
   - "cargo build --verbose"
   - "cargo test --verbose"
 notifications:

examples/hello_world.rs

@@ -66,7 +66,6 @@ fn main() {
     tokio::run(
         hello_world(homeserver_url.parse().unwrap(), room).map_err(|e| {
             dbg!(e);
-            ()
         }),
     );
 }