Fixed submit delay

Here's a patch for issue #26.

Now the values are more like what I would expect.
submissions:
attempt: 0, wait: 15
attempt: 1, wait: 30
attempt: 2, wait: 60
attempt: 3, wait: 120
attempt: 4, wait: 180
attempt: 5, wait: 240

status:
attempt: 0, wait: 30
attempt: 1, wait: 60
attempt: 2, wait: 120
attempt: 3, wait: 240
attempt: 4, wait: 480
attempt: 5, wait: 960
attempt: 6, wait: 1920
attempt: 7, wait: 3360
attempt: 8, wait: 4800
attempt: 9, wait: 6240