Use ledger print command instead of journal parsing

[ikorchynskyi]

These changes allow to use extended ledger syntax in the base journal, thus indirectly implementing #1. For example, the base journal may look like

include bank1.ledger
include bank2.ledger

and combined journal will be correctly shown on the web interface
Also, I've pinned the fido2 package version to the latest available <1.0 (0.9.3), as it seems that version >=1.0 has changed API and thus incompartible with the current ledger-web codebase.

[vifon]

Looks like what was hanging on the ledger-print branch for a few months. I was experimenting with this approach, but I'm not quite happy with the loss of the formatting, though it might be a justified sacrifice. I'll probably go with a per-user checkbox in the settings.

Good catch about FIDO2! I was very much experimenting with it when adding this feature and then forgot to pin the version.

I'll address these issues when I get some time.