Overlapping encounters

[dehall]

It's possible for two encounters on a patient's record to overlap. Seems like what's happening is a wellness encounter starts, then a disease module starts another encounter during the same timestep, then the subsequent modules that run are considered to be "in a wellness encounter" but when it calls getCurrentEncounter it gets that second one.

In terms of timestamps everything that occurs within the 2 modules generally makes sense, but if you group by encounter ID you get weird things like a patient who is diagnosed with hypertension but they don't have a blood pressure reading. (because the bp reading happens in wellness_encounters.json and the diagnosis happens in hypertension.json)