title: How to use `VueI18n` with typescript and `vue2.0`? `new VueI18n({..})` report `has no construct signatures` error
body: <p>I followed the <a href="https://kazupon.github.io/vue-i18n/installation.html#yarn" rel="nofollow noreferrer">installation guide</a> but getting error at <code>Vue.use(VueI18n);</code> and <code>const i18n = new VueI18n({...});</code>.</p>
  <p><code>Vue.use(VueI18n)</code> reports</p>
  <pre><code>No overload matches this call.
    Overload 1 of 2, '(plugin: PluginObject&lt;unknown&gt; | PluginFunction&lt;unknown&gt;, options?: unknown): VueConstructor&lt;Vue&gt;', gave the following error.
      Argument of type 'typeof import(&quot;.../node_modules/vue-i18n/dist/vue-i18n&quot;)' is not assignable to parameter of type 'PluginObject&lt;unknown&gt; | PluginFunction&lt;unknown&gt;'.
        Property 'install' is missing in type 'typeof import(&quot;.../node_modules/vue-i18n/dist/vue-i18n&quot;)' but required in type 'PluginObject&lt;unknown&gt;'.
    Overload 2 of 2, '(plugin: PluginObject&lt;any&gt; | PluginFunction&lt;any&gt;, ...options: any[]): VueConstructor&lt;Vue&gt;', gave the following error.
      Argument of type 'typeof import(&quot;.../node_modules/vue-i18n/dist/vue-i18n&quot;)' is not assignable to parameter of type 'PluginObject&lt;any&gt; | PluginFunction&lt;any&gt;'.
        Property 'install' is missing in type 'typeof import(&quot;.../node_modules/vue-i18n/dist/vue-i18n&quot;)' but required in type 'PluginObject&lt;any&gt;'.
      12 | import VueI18n from &quot;vue-i18n&quot;;
      13 | 
    &gt; 14 | Vue.use(VueI18n);
  </code></pre>
  <p>and
  <code>const i18n = new VueI18n({...});</code> reports</p>
  <pre><code>This expression is not constructable.
    Type 'typeof import(&quot;.../node_modules/vue-i18n/dist/vue-i18n&quot;)' has no construct signatures.
  </code></pre>
  <p>Here is my <code>Vue</code> instance.</p>
  <pre><code>new Vue({
    vuetify,
    router,
    i18n,
    render: (h) =&gt; h(App),
  }).$mount(&quot;#app&quot;);
  </code></pre>