feat: publicize doc implemetation

one/docs/demo/confirm-box/custom.vue

@@ -0,0 +1,41 @@
+<template>
+<article>
+  <veui-button @click="open = true">
+    Remove
+  </veui-button>
+  <veui-confirm-box
+    title="System Notification"
+    :open.sync="open"
+    @ok="ok"
+    @cancel="cancel"
+  >
+    <p>Are you sure to remove the item?</p>
+  </veui-confirm-box>
+</article>
+</template>
+
+<script>
+import { ConfirmBox, Button } from 'veui'
+import toast from 'veui/managers/toast'
+
+export default {
+  components: {
+    'veui-confirm-box': ConfirmBox,
+    'veui-button': Button
+  },
+  data () {
+    return {
+      open: false
+    }
+  },
+  methods: {
+    ok () {
+      this.open = false
+      toast.info('Confirmed')
+    },
+    cancel () {
+      toast.info('Canceled')
+    }
+  }
+}
+</script>