Removing obsolete tweaks from the Readme.
De-indenting lists.

GitHub has been redundantly rendering these within blockquotes.
Moving separate double colons into the previous paragraphs.
Removing extra indents from tables.

These, too, have been rendered in blockquotes.
More list tweaks
Updating links and version info.
Switching broken tables to definition lists.

The partially-broken tables haven't been touched, but perhaps should be.