Otherwise, we have a deadlock whenever the lock is forced: the app
will be restarted, and will find the lockfile is already there so it won't be
able to lock/unlock it. The supervisor will have the same problem.
So the solution is that, whenever we kill the app, that is the lock owner, we also unlock the file.
Select app to kill from DB within lock (otherwise, if some other part kills and restarts the app, the
containerId will have changed and the real container will not be removed).
Change the update cycle to go by appId instead of imageId.
Use Promise.using for lockFile locks and unlocks.
Now updates shouldn't stop if one of the apps fails to update
(it's a step towards better supporting multiple apps).
Forcing the lock now works.
Remove unnecessary require fs
Nicer assignment for s in joinErrorMessages
* gosuper in dockerignored folder
* correctly handle app not found in purge
* test formatting in test-gosuper
* Fix test-gosuper
* DRY up test-integration
* More work on the integration test
* Correctly get supervisor IP
* Use Fatal for test errors
* test-integration working separate from run-supervisor
* Use jenkins' JOB_NAME to identify and remove containers with their volumes
* Document testing procedure
* Document the assume-unchanged tip
* Use /mnt/root for data path
* Nicer secret assignment
* Restart app when purging
* Use log.Fatal to exit with status 1
* Quotes in entry.sh
* Use JSON for request body
* Handle errors for parseJsonBody
* Better error printing in main
* First attempt at testing nodesuper from Go
* Cleaner build
* Use ARCH to differentiate concurrent tests/builds
* Use --rm to autoremove containers
