[beta5] Change/review the way the DSFR library is integrated and required

Hello,
because the current code in 1.0-beta4 simply breaks the download of ui_suite_dsfr via composer (unless you add the package repository to the 'root' composer.json),
i propose first to drop the requirement at the heart of the problem. Here is a one line patch to starts with.

Hello,
i updated the README of the project to include an install section.
see MR 37.

thanks, i will have a look

Hello @just_like_good_vibes

Sorry for the delay, I was busy on other tasks. I am having a look now, and I will release the beta5 soon.

thank you Pierre, all the best