+ cherry-pick and rebase [DONE].
+
+* Binary diff detection fails if locale set to non English; even
+ GNU diff 2.8.1 and 2.8.7 in C locale say different things. At
+ least run diff under C locale (setenv LANG=C LC_ALL=C) for
+ 1.0. It might be better to have our own binary detection
+ logic, or even our own diff output without forking an external
+ diff. [The former _might_ make sense for 1.0, but the latter
+ is post 1.0].