Add some specification ideas.
Test::BusyBird::StatusStorage: test_storage_ordered(): add test for order of statuses with the same created_at and acked_at. The order is up to implementation, but it must not be changed by queries.
Input::Twitter: backend parameter for new() is now semi-optional, because the object might be used just for transformation. In that case, only 'apiurl' option is sufficient.
Add POD to App::BusyBird::Log.
Write POD, mainly of Timeline.