Fix typos (#348)

tokio-timer/src/timer/entry.rs

@@ -44,7 +44,7 @@ pub(crate) struct Entry {
     /// instant, this value is changed.
     state: AtomicU64,
 
-    /// When true, the entry is counted by `Inner` towards the max oustanding
+    /// When true, the entry is counted by `Inner` towards the max outstanding
     /// timeouts. The drop fn uses this to know if it should decrement the
     /// counter.
     ///
@@ -54,7 +54,7 @@ pub(crate) struct Entry {
     /// improve the struct layout. To do this, we must always allocate the node.
     counted: bool,
 
-    /// True wheen the entry is queued in the "process" stack. This value
+    /// True when the entry is queued in the "process" stack. This value
     /// is set before pushing the value and unset after popping the value.
     queued: AtomicBool,
 

tokio-timer/src/timer/mod.rs

@@ -320,7 +320,7 @@ where T: Park,
                 break;
             }
 
-            // Prcess the slot, either moving it down a level or firing the
+            // Process the slot, either moving it down a level or firing the
             // timeout if currently at the final (boss) level.
             self.process_expiration(&expiration);
 

tokio-timer/src/timer/registration.rs

@@ -40,7 +40,7 @@ impl Registration {
         let when = inner.normalize_deadline(deadline);
 
         if when <= inner.elapsed() {
-            // The deadline has already elapsed, ther eis no point creating the
+            // The deadline has already elapsed, there is no point creating the
             // structures.
             return Registration {
                 entry: Arc::new(Entry::new_elapsed(handle)),