Remove lib directory from version control

lib/plugins/ga.js

@@ -1,41 +0,0 @@
-(function () {
-// From https://github.com/egoist/vue-ga/blob/master/src/index.js
-function appendScript() {
-  var script = document.createElement('script');
-  script.async = true;
-  script.src = 'https://www.google-analytics.com/analytics.js';
-  document.body.appendChild(script);
-}
-
-function init(id) {
-  appendScript();
-  window.ga =
-    window.ga ||
-    function () {
-      (window.ga.q = window.ga.q || []).push(arguments);
-    };
-  window.ga.l = Number(new Date());
-  window.ga('create', id, 'auto');
-}
-
-function collect() {
-  if (!window.ga) {
-    init($docsify.ga);
-  }
-
-  window.ga('set', 'page', location.hash);
-  window.ga('send', 'pageview');
-}
-
-var install = function (hook) {
-  if (!$docsify.ga) {
-    console.error('[Docsify] ga is required.');
-    return
-  }
-
-  hook.beforeEach(collect);
-};
-
-$docsify.plugins = [].concat(install, $docsify.plugins);
-
-}());