Update and fix Trading212 parser

[vmartinv]

This introduces a few improvements to the Trading212 parser:

• Add support for a few new columns (keeping backward compatibility with the old format)
• Fix a bug when calculating the fees (I was able to spot this when I compared the calculated balance vs the actual balance in my account). Trading212 rounds off the price strangely so I just added an assert that checks that the discrepancy is less than 1 cent per share.
• Add one test with the new format
• Added a Stock Split, this event is actually missing in csv, I had to add it manually. I asked Trading212 to include it in the export but who knows when they will fix it.

[KapJI]

That could be a reason why you had mismatch here.

[vmartinv]

The reason there's a mismatch is because trading212 rounds the price / share.
Even when checking the transaction in the UI I get this discrepancy:
Sell 24 shares at $164.01 with exchange rate 1.25229 and £4.71 fees. Trading212 total says £3138.50. However,
24*164.01/1.25229-4.71=£3138.52

I believe there might be some implicit rounding both in the csv and in the UI. Some of them I was able to fetch more decimals from the UI and updating the csv. Others are unfixable, but since is just a few cents is not that important. I set it to a warning now when the discrepancy is more than 0.015 in the share price.
Ultimately, what matters is the £££ received/sent, which is what I'm using here.

[KapJI]

Looks good to me, thanks!