V2.2.1: Minor updates for Issues & PRs [Final 0.17 version]

This is a final update for the 2.1.0/2.2.0 version of LBTCftCL, which was the 2021 version of the course, focused largely on Bitcoin Core 0.17.0. It has been updated with a few fixes courtesy of Issues and PRs (thanks folks!), but has not seen any large-scale revision.

A new v3.0 is to follow, updated at least to 30.2 (and likely to 31 and it's to be a year-long project).

V2.2.0: Portuguese & Spanish Translations

This version officially releases our Portuguese & Spanish translations of the v2.0.1 release.

V2.1.0: I2P & Bitcoin 22

This release contains:

1. New I2P chapter, completely edited & integrated.
2. Fixes for a few recent versions of Bitcoin, up through Bitcoin 22.
3. Updates for recent changes in Linode setup & BItcoin Standup scripts.
4. A wide variety of fixes for minor issues exposed during the translation process.

V2.01: Minor PRs

Incorporates a number of minor PRs since the release of V2.0, fixing typos, fixing links, and adding a few clarifications.