Backport install-gosu-binary-wrapper from dockbuid

To ensure that our custom sudo wrapper is not
overwritten by a future re-install of sudo, it
is created in /usr/loca/bin

See https://github.com/dockbuild/dockbuild/issues/52

imagefiles/install-gosu-binary.sh

@@ -44,18 +44,3 @@ fi
 rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc
 
 chmod +x /usr/local/bin/gosu
-
-# verify that the binary works
-gosu nobody true
-
-
-cat << EOF >> /usr/bin/sudo
-#!/bin/sh
-
-# Emulate the sudo command
-
-exec gosu root:root "\$@"
-
-EOF
-
-chmod +x /usr/bin/sudo