So we print out invoice fees on the same line for those CSVs! This means
we have to do a little bit of gymnastics (but not too bad):
- we save the fee amount onto the income event now so we can use
it later
- we ignore every "invoice_fee" event for the koinly/cointracker
Note that since we're not skipping income events in the loops we also
move the newline character to the start of every `_entry` function so
skipped records dont incur empth lines.
Changelog-Added: bkpr: print out invoice fees on the same line for `koinly` and `cointracker` csv types
5146baa00b