Permission to merge preferences UI change

[Xan Lopez <xan gnome org>]

Hi guys, me again

after some months of back and forth we have decided that the minimum
font size pref in UI is pretty much a "allow me to shoot myself in the
foot" kind of thing for most people, so we'd like to remove it from
the UI and set a sane default that won't break the layout in random
pages. We'll leave the setting for those that want the old behavior.

Again, a bit late in the game, but if that's OK I'll merge this and
roll another release ASAP so that Shaun can still have the goodies
before he leaves.

The bug is: https://bugzilla.gnome.org/show_bug.cgi?id=644247

Cheers,

Xan