[Queue-2.0] Change up announcement loading
Summary
Currently, the announcements on top of a page are all loaded, but not directly shown. This leaves it to late javascript to show the announcement. This should be made such that announcements that are ignored are stored in the user session, so that they don't need to be shown at all and can be Thymeleaf loaded rather than Javascript loaded.
Implementation
Do not store in session, but instead of show then hide, start as hidden then show.
Edited by Ruben Backx