Move SKIPPD to HF and add forecast task

[nilsleh]

The paper of this dataset describes two tasks:

• nowcast: which is predicting the current power output given a single image
• forecast: predict the power output given a concatenated series of images

I used their script to generate the forecast version of this dataset and put both on HF for easier and faster download.

Edit:

Example Plot "Nowcast":

Example Plot "Forecast":

[adamjstewart]

Can you add example plots for both tasks so I can confirm that the plotting updates are good?

[adamjstewart]

One last typo fix and this should be good to merge!