feat: scope the no-options slot (#1083)

Resolves #1071, Resolves #1081

https://vue-select.org/guide/slots.html#improving-the-default-no-options-text

docs/.vuepress/components/BetterNoOptions.vue

@@ -0,0 +1,16 @@
+<template>
+  <v-select>
+    <template v-slot:no-options="{ search, searching }">
+      <template v-if="searching">
+        No results found for <em>{{ search }}</em>.
+      </template>
+      <em style="opacity: 0.5;" v-else>Start typing to search for a country.</em>
+    </template>
+  </v-select>
+</template>
+
+<script>
+export default {
+  name: 'BetterNoOptions',
+};
+</script>