Fix some test issues

At least on travis and my test box, adding the time offset to the instagram test fixed that api error.  It's because it uses that to create a min_timestamp parameter which is then used to pull data from tests/testdata/ and when I looked at it, the timestamp was off by 5 hours, which happened to be my timezone offset.

The ActivitySpike is the same thing I've seen before, where creating a Fixture in setup and then not nulling it out in teardDown (sometimes) causes the exit code to be 255 without causing an error.