Make Harbormaster buildable status more of a nice flexible map and less of a bunch of switch statements
Summary: Depends on D19063. Ref T13054. Prepare for the addition of a new PREPARING status by getting rid of the "scattered mess of switch statements" pattern of status management.
Test Plan: Searched/browsed buildables. Viewed buildables. Viewed revisions. Grepped for all affected symbols.
Subscribers: PHID-OPKG-gm6ozazyms6q6i22gyam
Maniphest Tasks: T13054
Differential Revision: https://secure.phabricator.com/D19064