C.UTF-8 locale not available on Centos
Currently the Centos 7 release build fails due to the
C.UTF-8 locale (which we use by default since b7a6b2f4) appears not to be available.
I found https://bugzilla.redhat.com/show_bug.cgi?id=902094 which seems to suggest that it may be available, but I can't work out exactly how one installs it. Only
C appears in
locales -a, even after removing
/etc/yum.conf and reinstalling
glibc-common (as suggested here).