Fix datahelper tests

I believe these tests broke with commit 0b010fe2e0f6a3dbcf6e33f13b14d6c7a3877fe8

At that point joinKey was passed through but the test wasn't expecting it so the deep.equals failed. However, I'm not sure about all the details of how the bolus conversion is supposed to work so maybe the test is failing because of a true bug. I suspect it is the test that is in error though.

I'm also rolling #120 into this PR.