refactor(core): adjust directory structure:

src/core/route/index.js

@@ -0,0 +1,17 @@
+import { ensureSlash } from './hash'
+
+export function routeMixin (Docsify) {
+  Docsify.prototype.$route = {
+    query: location.query || {},
+    path: location.path || '/',
+    base: ''
+  }
+}
+
+export function initRoute (vm) {
+  ensureSlash()
+  window.addEventListener('hashchange', () => {
+    ensureSlash()
+    vm.$fetch()
+  })
+}