cubicweb-document #640839 do not use cookie to set branch but an attribute on user [rejected]

the cookie is not convenient (albeit potentially useful for anonymous browsing) since we need branch info server side (and setting shared state tends to be brittle (not to talk about pbs. wrt unit tests))

prioritynormal
typebug
done in0.3.6
load0.000
load left0.000
closed by<not specified>