fix typo that's always bugging me

src/blocking_future.rs

@@ -38,7 +38,7 @@ impl<T> BlockingFuture<T> {
 }
 
 impl<T> Promise<T> {
-    pub(crate) fn fulfil(mut self, value: T) {
+    pub(crate) fn fulfill(mut self, value: T) {
         self.fulfilled = true;
         self.transition(State::Full(value));
     }

src/derived/slot.rs

@@ -780,7 +780,7 @@ where
                     // list, notify them that the value is available.
                     Some((new_value, ref cycle)) => {
                         for promise in waiting.into_inner() {
-                            promise.fulfil(WaitResult {
+                            promise.fulfill(WaitResult {
                                 value: new_value.clone(),
                                 cycle: cycle.clone(),
                             });