Questions from review of 1330

[stress-tess]

We wanted #1330 in this release if possible and none of my PR feedback was showstopping, so we went ahead and merged to give a few nights of testing. I wanted to capture my feedback here to make it doesn't get lost

• Update unique docstring to include groupable/ Sequences of groupable https://github.com/Bears-R-Us/arkouda/blob/a073707e095c6756d10b092eb7ee09c4eafba89d/arkouda/groupbyclass.py#L49-L50
• Update union1d to accept groupable like intersect1d
• it looks like the only place storeUniqueKeys is called is commented out https://github.com/Bears-R-Us/arkouda/blob/a073707e095c6756d10b092eb7ee09c4eafba89d/src/UniqueMsg.chpl#L71

[kaydoh]

I like the new label for questions

[stress-tess]

@reuster986, when you get a chance, could you take a look at these questions from the review of #1330