deprecated function call in generate_samples

[powerspowers]

I am a bit lame with GitHub pull requests so here is a note that a call is deprecated:

generate_samples.py:126: DeprecationWarning: imsave is deprecated!
imsave is deprecated in SciPy 1.0.0, and will be removed in 1.2.0.
Use imageio.imwrite instead.
ss_image.squeeze(0).permute(1, 2, 0).cpu())

[akanimax]

@powerspowers,

Sure, it's always better to remove the deprecated packages. I'll update the call soon.
Thanks! 😄

Cheers 🍻!
@akanimax