refactor(core): adjust directory structure:

src/core/route/hash.js

@@ -0,0 +1,24 @@
+import { cleanPath, getLocation } from './util'
+
+export function ensureSlash () {
+  const path = getHash()
+  if (path.charAt(0) === '/') return
+  replaceHash('/' + path)
+}
+
+export function getHash () {
+  // We can't use window.location.hash here because it's not
+  // consistent across browsers - Firefox will pre-decode it!
+  const href = window.location.href
+  const index = href.indexOf('#')
+  return index === -1 ? '' : href.slice(index + 1)
+}
+
+function replaceHash (path) {
+  const i = window.location.href.indexOf('#')
+  window.location.replace(
+    window.location.href.slice(0, i >= 0 ? i : 0) + '#' + path
+  )
+}
+
+// TODO 把第二个 hash 转成 ?id=