* Add PluginInstaller class
* Redirect to referring page if one exists
* Store message and show after redirect
* Add transient notices feature
* Fix default and empty state of notices
* Use TransientNotices to display plugin notices
* Add transient notices readme
* Add feature unit tests
* Update notice queue client-side
* Add filter to queued option prior to notice creation
* Use the core/notices2 data store
* Fix filtered queued notices
* Add methods to get individual notices and queue
* Allow user ID specific notices
* Remove errant script asset dependencies
* Add user ID property to docs
* Use preloaded option instead of window var
* Refactor transient notices to directly use option instead of state
* Show error message from WP_Error in plugin installer
* Add tests around notice queue in client
* Add changelog entry
Joshua T Flowers