Use the new mediacounts in baglama

[Federico Leva]

I'd like to start using the https://wikitech.wikimedia.org/wiki/Analytics/Data/Mediacounts data for our GLAM categories as soon as possible. Magnus, if you tell me what approach you prefer I'll do my best to code it.

From my first inspections on a couple categories (BEIC https://lists.wikimedia.org/pipermail/analytics/2015-March/003695.html and WLM-IT http://mailman.wikimedia.it/pipermail/wlm/2015-March/001743.html ), I think "total transfers" is too high and too similar to what we already have (pageviews), while columns 11–14 (big thumbs) and perhaps "raw transfers" are most interesting and could be summed, producing a new value to present alongside the "traditional" one.