[WEBSITE] Add man pages for the 0.22.0 version

Summary:
This adds the man pages for version 0.22.0 as part of the user
documentation.

Depends on D7251.

Test Plan: Build and navigate through Documentation => Man pages

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Subscribers: deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D7252