Add smol-rs logo (#47)

Author: notgull

src/lib.rs

@@ -71,6 +71,12 @@
 #![warn(missing_docs, missing_debug_implementations, rust_2018_idioms)]
 #![doc(test(attr(deny(rust_2018_idioms, warnings))))]
 #![doc(test(attr(allow(unused_extern_crates, unused_variables))))]
+#![doc(
+    html_favicon_url = "https://raw.githubusercontent.com/smol-rs/smol/master/assets/images/logo_fullsize_transparent.png"
+)]
+#![doc(
+    html_logo_url = "https://raw.githubusercontent.com/smol-rs/smol/master/assets/images/logo_fullsize_transparent.png"
+)]
 
 extern crate alloc;