Pinned statuses (#4675)

* Pinned statuses

* yarn manage:translations

app/javascript/mastodon/locales/ar.json

@@ -168,6 +168,7 @@
   "status.mention": "أذكُر @{name}",
   "status.mute_conversation": "Mute conversation",
   "status.open": "وسع هذه المشاركة",
+  "status.pin": "Pin on profile",
   "status.reblog": "رَقِّي",
   "status.reblogged_by": "{name} رقى",
   "status.reply": "ردّ",
@@ -179,6 +180,7 @@
   "status.show_less": "إعرض أقلّ",
   "status.show_more": "أظهر المزيد",
   "status.unmute_conversation": "Unmute conversation",
+  "status.unpin": "Unpin from profile",
   "tabs_bar.compose": "تحرير",
   "tabs_bar.federated_timeline": "الموحَّد",
   "tabs_bar.home": "الرئيسية",