pjf/masterwork-dwarf-fortress — pull request #120 by splintermind (2014-01-15 15:50:40+00:00)
Title: Removes obsolete siren stuff.

According to Meph (http://www.bay12forums.com/smf/index.php?topic=125630.msg4918202#msg4918202) the air pressure research was intended for the siren building, both of which have been removed. This also comes with some announcements and blueprints that have also been cleaned up.