non-tuple sequence warning

[scfleming]

I get the following when running ggui:

/Users/fleming/anaconda3/lib/python3.6/site-packages/glue/core/component.py:87: FutureWarning:

Using a non-tuple sequence for multidimensional indexing is deprecated; use arr[tuple(seq)] instead of arr[seq]. In the future this will be interpreted as an array index, arr[np.array(seq)], which will result either in an error or a different result.