.hgignore: add vendor tree composer.json: new packages plugins/thunderbird_labels/thunderbird_labels.php: change hook and RFC822 use wrt whitelisting to avoid deprecated stuff index.php: commented debugging hooks others: new releases of vendor packages?

-- Updates from version 0.5.x

ALTER TABLE contacts ADD words TEXT NULL;
CREATE INDEX contactgroupmembers_contact_id_idx ON contactgroupmembers (contact_id);

TRUNCATE messages;
TRUNCATE cache;