Show appropriate feature flags in docs

src/libstd/thread/mod.rs

@@ -367,7 +367,8 @@ pub fn spawn<F, T>(f: F) -> JoinHandle<T> where
 /// a join before any relevant stack frames are popped:
 ///
 /// ```rust
-/// # #![feature(scoped)]
+/// #![feature(scoped)]
+///
 /// use std::thread;
 ///
 /// let guard = thread::scoped(move || {
@@ -447,7 +448,8 @@ pub fn panicking() -> bool {
 /// # Examples
 ///
 /// ```
-/// # #![feature(catch_panic)]
+/// #![feature(catch_panic)]
+///
 /// use std::thread;
 ///
 /// let result = thread::catch_panic(|| {

src/libstd/thread/scoped_tls.rs

@@ -24,7 +24,8 @@
 //! # Examples
 //!
 //! ```
-//! # #![feature(scoped_tls)]
+//! #![feature(scoped_tls)]
+//!
 //! scoped_thread_local!(static FOO: u32);
 //!
 //! // Initially each scoped slot is empty.
@@ -136,7 +137,8 @@ impl<T> ScopedKey<T> {
     /// # Examples
     ///
     /// ```
-    /// # #![feature(scoped_tls)]
+    /// #![feature(scoped_tls)]
+    ///
     /// scoped_thread_local!(static FOO: u32);
     ///
     /// FOO.set(&100, || {
@@ -189,7 +191,8 @@ impl<T> ScopedKey<T> {
     /// # Examples
     ///
     /// ```no_run
-    /// # #![feature(scoped_tls)]
+    /// #![feature(scoped_tls)]
+    ///
     /// scoped_thread_local!(static FOO: u32);
     ///
     /// FOO.with(|slot| {