chore: add fullScreen

Author: Simon he

src/fullScreen.ts

@@ -0,0 +1,8 @@
+export function fullScreen() {
+  const el: any = document.documentElement;
+  const rfs = el.requestFullScreen || el.webkitRequestFullScreen || el.mozRequestFullScreen || el.msRequestFullScreen;
+  if (rfs)
+    rfs.call(el);
+  else
+    alert("浏览器不支持全屏");
+}