* Add new Elephant Friend images. Use them in ListsActivity.
* Add error images to AccountListFragment
* Add error images to Timeline & Notifications fragment. Needs rework.
* Introduce BackgroundMessageView. Use it in AccountList.
* Use correct button style for BackgroundMessageView
Co-Authored-By: charlag <charlag@tutanota.com>
* Use BackgroundMessageView
* Add BackgroundMessageView docs
* Re-color and document elephants
* Apply feedback, disable refresh when error is shown
* Fix string typo