Delay starting the girder process after vagrant start

[brianhelba]

On at least OSX, it appears as though Supervisor may be starting Girder before the shared isic_archive directory is mounted. This causes Girder to fail to load the isic_archive plugin. Restarting supervisor manually after vagrant up is a workaround.

The fix is to configure supervisor to delay the initial automatic starting of Girder by a few seconds, by which time the directory should be mounted. However, during a normal user-initiated restart of Girder, the delay should not happen.