Demo fails

[MasahiroOgawa]

I tried to run demo, but it failed with this error;

    from .pykdtree.kdtree import KDTree
  File "__init__.pxd", line 885, in init pykdtree.kdtree
ValueError: numpy.ufunc has the wrong size, try recompiling. Expected 192, got 216

[MasahiroOgawa]

Probably this is caused by numpy version (automl/auto-sklearn#621).
I will try to fix this.

[MasahiroOgawa]

Finally I solve the problem using docker environment.
See #9

[MasahiroOgawa]

Actually it worked on GTX1060, but it failed on GTX3070.
But finally I fixed it and confirmed to finish demo even native (witout docker environment).
I updated the pull request.
So please check the above #9 pull request.

[m-niemeyer]

Thanks @MasahiroOgawa for creating the respective docker environment - I merged your pull request now!