Installation requirements could be more specific (ROOT version)

[lobis]

Some colleages that were installing REST-for-Physics for the first time understood from the documentation that REST is compatible with ROOT >6 but it failed to install on v6.22.02 even though it was compield with c++17 support.

We should define a specific minimum version of root that is supported and also add it to our CI, atleast compile REST on this.

[jgalan]

In principle it should compile also with ROOT 6.22, why it doesn't?

We should try to encourage the use of a particular version, e.g. the one defined by the script ./installROOT.sh, as described here: https://rest-for-physics.github.io/installation.

Perhaps that documentation could be improved to emphasise and encourage the installation of a particular version, and particular compilation flags. Those found at the script installROOT.sh.

[jgalan]

Shall we close this issue?