Add fn: add-queue-token! for use with the REPL
add clj-time dep
add gangway schema to applications, pass db-conn to helmsman-definition
pull token from datomic and make sure is is not expired
Modify helmsman-definition to accept db-connection and pass it to liberator-resources map
update tests to generate a new token, add it to datomic, and use the generated token
add schema to store tokens in datomic