Finish adding delete board feature

client/components/boards/boardHeader.jade

@@ -240,6 +240,8 @@ template(name="archiveBoardPopup")
 
 template(name="deleteBoardPopup")
   p {{_ 'delete-board-pop'}}
+  unless archived
+    p {{_ 'board-delete-suggest-archive'}}
   button.js-confirm.negate.full(type="submit") {{_ 'delete'}}
 
 template(name="outgoingWebhooksPopup")

i18n/en.i18n.json

@@ -470,5 +470,9 @@
     "editCardReceivedDatePopup-title": "Change received date",
     "editCardEndDatePopup-title": "Change end date",
     "assigned-by": "Assigned By",
-    "requested-by": "Requested By"
+    "requested-by": "Requested By",
+    "board-delete-notice": "Deleting is permanent. You will lose all lists, cards and actions associated with this board.",
+    "board-delete-pop": "All lists, cards, labels, and activities will be removed and you won't be able to recover the board contents. There is no undo.",
+    "board-delete-suggest-archive": "You can archive a board to remove it from the the active boards and preserve the activity.",
+    "deleteBoardPopup": "Delete Board?"
 }