See merge request nexedi/slapos!1251

Includes buildout, configuration, test, and resiliency support

See merge request nexedi/slapos!1298

Allow ffmpeg to get the correct libvpx path

Using "Sort Lines Ascending" from Theia or `:'<,'>!sort -f` from vim
produce this diff.

See merge request nexedi/slapos!1279

See merge request nexedi/slapos!1295

This is more coherent with other SR. At some point, we hsould get this
file from nginx installation.

See merge request nexedi/slapos!1294

depends on nexedi/erp5!1695

See merge request nexedi/slapos!1290