Update sklearn example

[danielfrg]

Updating the scikit-learn sample app:

• Updated the workflow to the new UI, forms and stuff
• Added instructions on the environment selection
• Updated the dependencies so it works with the python 3.7 environment
• Changed the serialisation format to joblib, this is the recommended by scikit-learn
• Added two query options, real time predict and batch based on a file

[koverholt]

Thanks, LGTM!

In the current/older version with the pickle file, I ended up pinning numpy and scipy in the requirements.txt for maximum reproducibility. Do you see a need to do that here as well?

Also, thanks for including the specific language and environment to use!

[danielfrg]

Yeah, I think that makes sense, I will pin numpy. Is there a reason you included scipy?

[koverholt]

I include numpy and scipy both since they are deps of sklearn. In theory pinning only sklearn would handle this, but you know how finicky these things can be.

For example, in the current version this works:

algorithmia>=1.0.0,<2.0
numpy==1.11.3
scipy==1.2.1
scikit-learn==0.17.1

but if you remove scipy, it will attempt to install the latest version of scipy and things won't work.

[danielfrg]

Thanks for the review! added scipy pin and fixes your suggestions

[bnlb]

lgtm!