refactor: Update for alpenhorn data index changes

[ketiltrout]

See: radiocosmology/alpenhorn#365 and radiocosmology/alpenhorn#369

• Adds the new StorageHost table.
• Updates StorageNode:
  • remove address and username (moved to StorageHost)
  • change host to a foreign key to the StorageHost table.
  • replace storage_type enum with archive boolean.
  • delete obsolete fields suspect and min_delete_age_days
• Update util.update_storage:
  • handle StorageHost creation
  • Delete now-unused cedar_offload node.
  • Update node names for fir

[ketiltrout]

I have added the new columns to the production database (without removing the old columns):

-- Add archive column to the storagenode table
START TRANSACTION;
ALTER TABLE storagenode ADD COLUMN IF NOT EXISTS archive TINYINT(1) NOT NULL DEFAULT 0 AFTER suspect;
UPDATE storagenode set archive=1 WHERE storage_type='A';
COMMIT;

-- Create and populate the storagehost table
START TRANSACTION;
CREATE TABLE storagehost (id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY, name VARCHAR(64) NOT NULL UNIQUE, username VARCHAR(64) DEFAULT NULL, address varchar(64) DEFAULT NULL, notes LONGTEXT);
INSERT INTO storagehost VALUES(1, "gong", "chimeadmin", "hac1-nren.chimenet.ca", "At the CHIME telescope.  Data is on gong, but the alpenhorn daemon runs on wind.");
INSERT INTO storagehost VALUES(2, "fir", "chimedat", "robot.fir.alliancecan.ca", "WestGrid compute cluster.");
INSERT INTO storagehost VALUES(3, "scinet", "chimedat", "robot3.scinet.utoronto.ca", "SciNet compute cluster.  Access via trillium.");
COMMIT;

-- Add a host_id foreign key to the storagenode table
START TRANSACTION;
ALTER TABLE storagenode ADD COLUMN IF NOT EXISTS host_id INT DEFAULT NULL AFTER host;
ALTER TABLE storagenode ADD CONSTRAINT storagenode_ibfk_2 FOREIGN KEY (host_id) REFERENCES storagehost (id);
UPDATE storagenode SET host_id=1 WHERE host="wind" AND active=1;
UPDATE storagenode SET host_id=2 WHERE host="cedar5" AND active=1;
UPDATE storagenode SET host_id=3 WHERE host="scinet" AND active=1;
COMMIT;