Occasional Postgres Errors on Gameboard Save

[jsharkey13]

I don't know if this is new error, or an old one. We should check whether the ID exists on the board builder page already; so unless that has stopped working, this may be something new.

[2017-07-17 14:58:51] [ERROR] GameboardsFacade:393 - Database Error whilst trying to save the gameboard.
uk.ac.cam.cl.dtg.segue.dao.SegueDatabaseException: Postgres exception
    at uk.ac.cam.cl.dtg.isaac.dao.GameboardPersistenceManager.saveGameboard(GameboardPersistenceManager.java:576)
    at uk.ac.cam.cl.dtg.isaac.dao.GameboardPersistenceManager.saveGameboardToPermanentStorage(GameboardPersistenceManager.java:185)
    at uk.ac.cam.cl.dtg.isaac.api.managers.GameManager.permanentlyStoreGameboard(GameManager.java:820)
    at uk.ac.cam.cl.dtg.isaac.api.managers.GameManager.saveNewGameboard(GameManager.java:538)
    at uk.ac.cam.cl.dtg.isaac.api.GameboardsFacade.createGameboard(GameboardsFacade.java:384)
    at uk.ac.cam.cl.dtg.isaac.api.GameboardsFacade.updateGameboard(GameboardsFacade.java:462)
...
Caused by: org.postgresql.util.PSQLException: ERROR: duplicate key value violates unique constraint "gameboard-id-pkey"
  Detail: Key (id) already exists.