Improve examples for async() and await()

Author: clue

README.md

@@ -80,11 +80,13 @@ asynchronously without blocking:
 ```php
 Loop::addTimer(0.5, React\Async\async(function() {
     echo 'a';
-    React\async\await(React\Promise\Timer\sleep(1.0));
+    React\Async\await(React\Promise\Timer\sleep(1.0));
     echo 'c';
 }));
 
-Loop::addTimer(1.0, fn() => echo 'b');
+Loop::addTimer(1.0, function() {
+    echo 'b';
+});
 
 // prints "a" at t=0.5s
 // prints "b" at t=1.0s
@@ -104,7 +106,9 @@ Loop::addTimer(0.5, React\Async\async(function() {
     echo 'c';
 }));
 
-Loop::addTimer(1.0, fn() => echo 'b');
+Loop::addTimer(1.0, function() {
+    echo 'b';
+});
 
 // prints "a" at t=0.5s
 // prints "c" at t=1.5s: Correct timing, but wrong order
@@ -249,11 +253,13 @@ outside this function can be executed asynchronously without blocking:
 ```php
 Loop::addTimer(0.5, React\Async\async(function() {
     echo 'a';
-    React\async\await(React\Promise\Timer\sleep(1.0));
+    React\Async\await(React\Promise\Timer\sleep(1.0));
     echo 'c';
 }));
 
-Loop::addTimer(1.0, fn() => echo 'b');
+Loop::addTimer(1.0, function() {
+    echo 'b';
+});
 
 // prints "a" at t=0.5s
 // prints "b" at t=1.0s

src/functions.php

@@ -21,11 +21,13 @@
  * ```php
  * Loop::addTimer(0.5, React\Async\async(function() {
  *     echo 'a';
- *     React\async\await(React\Promise\Timer\sleep(1.0));
+ *     React\Async\await(React\Promise\Timer\sleep(1.0));
  *     echo 'c';
  * }));
  *
- * Loop::addTimer(1.0, fn() => echo 'b');
+ * Loop::addTimer(1.0, function() {
+ *     echo 'b';
+ * });
  *
  * // prints "a" at t=0.5s
  * // prints "b" at t=1.0s
@@ -45,7 +47,9 @@
  *     echo 'c';
  * }));
  *
- * Loop::addTimer(1.0, fn() => echo 'b');
+ * Loop::addTimer(1.0, function() {
+ *     echo 'b';
+ * });
  *
  * // prints "a" at t=0.5s
  * // prints "c" at t=1.5s: Correct timing, but wrong order
@@ -229,11 +233,13 @@ function async(callable $function): callable
  * ```php
  * Loop::addTimer(0.5, React\Async\async(function() {
  *     echo 'a';
- *     React\async\await(React\Promise\Timer\sleep(1.0));
+ *     React\Async\await(React\Promise\Timer\sleep(1.0));
  *     echo 'c';
  * }));
  *
- * Loop::addTimer(1.0, fn() => echo 'b');
+ * Loop::addTimer(1.0, function() {
+ *     echo 'b';
+ * });
  *
  * // prints "a" at t=0.5s
  * // prints "b" at t=1.0s