Add soft delete for statuses for instant deletes through API (#11623)

* Add soft delete for statuses to allow them to appear instant

* Allow reporting soft-deleted statuses and show them in the admin UI

* Change index for getting an account's statuses

db/migrate/20190819134503_add_deleted_at_to_statuses.rb

@@ -0,0 +1,5 @@
+class AddDeletedAtToStatuses < ActiveRecord::Migration[5.2]
+  def change
+    add_column :statuses, :deleted_at, :datetime
+  end
+end