Terminator 1.90 released

Written for Terminator by Stephen Boddy on 2016-11-23

OK folks. This is your chance. An honest to goodness (pre-)release of the GTK3 version of Terminator. Please use this if you possibly can, and provide fixes if you have the skills. If you have a bug that you can't fix and you think it is serious enough that it really should be fixed before the big 2.0, then assign it the tag "release-blocker". If I agree, I'll target it to the milestone.

Looking here for show-stoppers, as I'm well aware that Terminator has lots of strange little nooks and crannies that display strange behaviour when it's the second Thursday of a month with 30 days.