docs: remove all usages of static closure syntax and update readme

examples/core_reference/task.rs

@@ -42,19 +42,19 @@ pub static Example: Component = |cx| {
         div {
             h1 {"count is {count}"}
             button {
+                onclick: move |_| task.stop(),
                 "Stop counting"
-                onclick: move |_| task.stop()
             }
             button {
+                onclick: move |_| task.resume(),
                 "Start counting"
-                onclick: move |_| task.resume()
             }
             button {
-                "Switch counting direcion"
                 onclick: move |_| {
                     direction *= -1;
                     task.restart();
                 }
+                "Switch counting direcion"
             }
         }
     })