update dependencies and add tag function

ts/index.ts

@@ -10,6 +10,7 @@ import {build} from "./npmci.build"
 import {install} from "./npmci.install";
 import {publish} from "./npmci.publish";
 import {prepare} from "./npmci.prepare";
+import {tag, retag} from "./npmci.tag";
 import {test} from "./npmci.test";
 import {trigger} from "./npmci.trigger";