Feat: Trade counts and trading volume per account

[bvotteler]

Resolves #87 Resolves #88

Adding more cumulative volumes (not converted to BTC/USDT yet):

• [x] Total trading volume
• [x] Trading volume per account

Adding cumulative trade counts:

• [x] Total trade count
• [x] Trade count per account

Todo:

• [x] Test against kintnet
• [x] Test against kintsugi
• [x] Test against interlay