Improve rake task mconf:stats, refs #796
Improve rake task mconf:stats, refs #796

Shows now a single table with stats for all models together and also
columns with the sum of values over time.

arrivu/web-conf,m-narayan/agora-conf,arrivu/web-conf,m-narayan/agora-conf,arrivu/web-conf,m-narayan/agora-conf,m-narayan/agora-conf,arrivu/web-conf,arrivu/web-conf,m-narayan/agora-conf,m-narayan/agora-conf,m-narayan/agora-conf,arrivu/web-conf,arrivu/web-conf