Switch from 'wmf' to 'wmf_raw' as hive database for raw data

Discussion for the switch to wmf_raw can be found in

  http://bots.wmflabs.org/~wm-bot/logs/%23wikimedia-analytics/20140716.txt

between 18:31:24 and 18:53:12.

Change-Id: Icedb816a305f32ace4d5853268bd8b359f1d930a