Remote custom emojis (#3074)

* Remote custom emojis

* んほおおおおお

src/remote/activitypub/misc/get-emoji-names.ts

@@ -0,0 +1,6 @@
+import parse from '../../../mfm/parse';
+
+export default function(text: string) {
+	if (!text) return [];
+	return parse(text).filter(t => t.type === 'emoji').map(t => (t as any).emoji);
+}