Revert "Merge branch 'sh-upgrade-charlock-holmes' into 'master'"

This reverts merge request !1647 (merged)

charlock_holmes v0.7.7 doesn't build on CentOS 6 because the new changes enforce -std=c++11, which isn't valid on G++ prior to v4.7.

We'll need to send an upstream patch if we want to disable this flag.

Part of gitlab#37095 (closed).