Add precision recall and F1 scores

[MrInformatic]

I've added precision recall and F1 Scores to all tasks that only Featured accuracy scores. In which shape or form should I submit the Feature?

[ZeweiChu]

Thanks for doing that! Would you send a pull request to this repo with the added F1 scores in "section Experiments"? You may add your name somewhere in the end of the README file to indicate your contribution to this table.

[MrInformatic]

I've only added the code to calculate the precision, recall and F1 scores and not actually recalculated the scores. Is there a pull request template for this repository?