pyramid-cubicweb #4870347 Speed-up repo_connect [resolved]

The main bottleneck is repo.build_user, which could be cached.

prioritynormal
typebug
done in0.3.0
load left0.000
closed by#d92a608c1a16 [core] Use tools.cached_user_build for better performances
patch[core] Use tools.cached_user_build for better performances [applied][doc] Document tools [applied][tools] Provide a faster build_user [applied]