Build / run dependencies vs Docker

[Axel-Naumann]

Can we generate the dependencies page from the docker package dependencies?

[eguiraud]

Most of our Dockerfiles do not build ROOT -- arch, fedora, gentoo, conda just install with the corresponding package manager. Centos7 and Ubuntu currently build ROOT but we would like to switch them to using the fedora package and ROOT's .deb file respectively, because we cannot compile ROOT on Dockerhub, i.e. we can't easily produce Ubuntu and Centos7 docker images if they have to build ROOT from scratch.

So at most, Dockerfiles will have runtime dependencies for Ubuntu, maybe Centos7, and the lists won't be complete because not all features are ON.

The docs would additionally need compile-time dependencies and each external should list what package it requires.