Implement automatic chart generation after backtesting is complete

[kevin-li-195]

Must use Haskell library because of reasons.

[tsani]

Maybe not automatic chart generation. We should make the output of Jafar should be in some kind of language-agnostic format (JSON with a strict schema), so that we have the data to play with in different tools. Of course, we should make some kind of plotting tool (in Haskell) that accepts an input in this format to compare backtesting results