Fix typos

Author: jayvdb

Diff for: CHANGELOG.md

@@ -686,9 +686,9 @@ use async_std::prelude::*;
 use async_std::task;
 
 task::spawn(async {
-    let x = fibonnacci(1000); // Do expensive work
+    let x = fibonacci(1000); // Do expensive work
     task::yield_now().await;  // Allow other tasks to run
-    x + fibonnacci(100)       // Do more work
+    x + fibonacci(100)       // Do more work
 })
 ```
 

Diff for: src/stream/successors.rs

@@ -42,7 +42,7 @@ pin_project! {
     ///
     /// This stream is constructed by [`successors`] function
     ///
-    /// [`successors`]: fn.succssors.html
+    /// [`successors`]: fn.successors.html
     #[cfg(feature = "unstable")]
     #[cfg_attr(feature = "docs", doc(cfg(unstable)))]
     #[derive(Debug)]