RasterEquidistantMetricSpace errors with scipy 1.0

[mmaelicke]

This line is not supported anymore with scipy 1.0:

https://github.com/mmaelicke/scikit-gstat/blob/22ff51ce798e0bfb4280392b32cbf9d9a480d89a/skgstat/MetricSpace.py#L786

see also https://github.com/scipy/scipy/issues/8338

With #185 the bug is fixed for now, as the old, slower code is used again. If we want to change the dok matrix directly we need to do that via fancy indexing. @rhugonnet if I remember correctly, you implemented this class, right? Can you comment on this?

I just commented out the non-working solution, so to close this issue we could either remove the commented code, or implement a better solution.