fix(doc): rename doc_cfg guard to docsrs, rust-lang/cargo#13875 (#45)

Author: zvolin

Cargo.toml

@@ -62,4 +62,4 @@ log = "0.4.18"
 wasm-bindgen = ["futures-timer/wasm-bindgen", "instant/wasm-bindgen"]
 
 [package.metadata.docs.rs]
-rustdoc-args = ["--cfg", "docs_rs"]
+rustdoc-args = ["--cfg", "docsrs"]

src/lib.rs

@@ -1,4 +1,4 @@
-#![cfg_attr(docs_rs, feature(doc_cfg))]
+#![cfg_attr(docsrs, feature(doc_cfg))]
 #![doc = include_str!("../README.md")]
 
 use std::sync::Arc;