feat: publicize doc implemetation

one/docs/demo/radio-group/default.vue

@@ -0,0 +1,62 @@
+<template>
+<article>
+  <section>
+    <h4>Normal size</h4>
+    <veui-radio-group
+      v-model="flavor"
+      :items="flavors"
+    />
+    <p>Checked: {{ readable }}</p>
+  </section>
+  <section>
+    <h4>Small size</h4>
+    <veui-radio-group
+      v-model="flavor"
+      ui="s"
+      :items="flavors"
+    />
+    <p>Checked: {{ readable }}</p>
+  </section>
+</article>
+</template>
+
+<script>
+import { RadioGroup } from 'veui'
+
+export default {
+  components: {
+    'veui-radio-group': RadioGroup
+  },
+  data () {
+    return {
+      flavor: null,
+      flavors: [
+        { value: 'LATTE', label: 'Latte' },
+        { value: 'MOCHA', label: 'Mocha' },
+        { value: 'AMERICANO', label: 'Americano' }
+      ]
+    }
+  },
+  computed: {
+    flavorLabelMap () {
+      return this.flavors.reduce((map, { value, label }) => {
+        map[value] = label
+        return map
+      }, {})
+    },
+    readable () {
+      return this.flavorLabelMap[this.flavor] || '-'
+    }
+  }
+}
+</script>
+
+<style lang="less" scoped docs>
+section {
+  margin-bottom: 20px;
+}
+
+h4 {
+  margin-top: 0;
+}
+</style>