Lists (#5703)

* Add structure for lists

* Add list timeline streaming API

* Add list APIs, bind list-account relation to follow relation

* Add API for adding/removing accounts from lists

* Add pagination to lists API

* Add pagination to list accounts API

* Adjust scopes for new APIs

- Creating and modifying lists merely requires "write" scope
- Fetching information about lists merely requires "read" scope

* Add test for wrong user context on list timeline

* Clean up tests

app/models/session_activation.rb

@@ -3,15 +3,15 @@
 #
 # Table name: session_activations
 #
-#  id                       :bigint           not null, primary key
-#  user_id                  :bigint           not null
+#  id                       :integer          not null, primary key
 #  session_id               :string           not null
 #  created_at               :datetime         not null
 #  updated_at               :datetime         not null
 #  user_agent               :string           default(""), not null
 #  ip                       :inet
-#  access_token_id          :bigint
-#  web_push_subscription_id :bigint
+#  access_token_id          :integer
+#  user_id                  :integer          not null
+#  web_push_subscription_id :integer
 #
 
 #  id              :bigint           not null, primary key