Priority Announcement Changes

-Centcom announcement proc merged with generic priority announcement proc
-Re-added the Captain Announces accompanied by a new pleasant sound, instead of the generic priority announcement
-Captain Announcements will automatically generate a newscaster article
-Priority announcements without any defined accompanying sound will play a generic "Attention" soundbyte as an audio cue
-Communications consoles will display who is currently logged in
Fixed non-captains not registering their ID to the Comms console
-Merged centcom and announcements news channel into a single "Station Announcements" channel
-RC Announcements now produce news stories, too
-The AI may now make priority announcements via communications console that emulates the automated messages
Converted early shuttle launch notices to priority announcements
Merge branch 'master' of https://github.com/tgstation/-tg-station into announcements
Added a make_announcement proc to reduce duplicated code
Added a canUseTopic()
Merge pull request #3645 from Ikarrus/announcements

Priority Announcement Changes