Enable Flow on mw.org usability research test page

For 2014-11-03 SWAT, probably

Change-Id: I076fa65538370090132f51be6112e78564abe68e
Enable Flow on officewiki on test page Talk:Flow

https://www.loomio.org/d/rTbveB9O/dogfood-flow-on-officewiki was
landslide vote in favor of '"Dogfood" Flow on OfficeWiki', this is first
step towards that.

Change-Id: Ia47d9becc2989b3976e2f1086c40f4d026038792
Merge "Enable Flow on officewiki on test page Talk:Flow"
Merge "Enable Flow on mw.org usability research test page"