Apply the asciidoc + bootstrap approach used with 42ity.org

[jimklimov]

Reminder from @aquette : improvement over the 1rst gen website generator (as currently used with networkupstools.org)

For asciidoc + bootstrap, it mainly relies on the J's/ subdir plus this asciidoc conf for bootstrap:
https://github.com/42ity/42ity-org-website/blob/master/bootstrap.conf

And a bit of salt in the Makefile too.

As per http://laurent-laville.org/asciidoc/bootstrap/, the version in 42ity is the latest (2015 😕). So no need to update the integration

UPDATE: Some more links for reference:

• https://github.com/twbs/bootstrap
• https://getbootstrap.com/
• https://getbootstrap.com/docs/5.3/getting-started/introduction/
• https://github.com/llaville/asciidoc-bootstrap-backend - An AsciiDoc backend that renders the AsciiDoc source as HTML5 in the style of Bootstrap.
  • This repository has been archived by the owner on Sep 13, 2020. It is now read-only.
• http://laurent-laville.org/asciidoc/bootstrap/

[aquette]

see #31

[jimklimov]

Code samples in bootstrap rendering look odd, like doubly-quoted replies (with the left bar).

Actually, the "NOTE" sections also have that bar (but this could at least be hand-waved away as separating the "note" icon from its block of text).

@aquette : any ideas if this is about something in CSS invovled?