Make all subdirectories under /etc/<appname> executable by default

In Riak, when the /etc/riak/snmp directory was created it did
not have the +x flag set so riak could not start.  The +X flag
will inherit the executable status of its parent files so only
directories will be set.

priv/templates/deb/postinst

@@ -31,6 +31,7 @@ chown -R {{package_install_user}}:{{package_install_group}} /etc/{{package_insta
 
 chmod 0755 /var/run/{{package_install_name}} /etc/{{package_install_name}}
 chmod 0644 /etc/{{package_install_name}}/*
+chmod -R +X /etc/{{package_insall_name}}
 chmod 0755 /usr/lib/{{package_install_name}}/lib/env.sh
 
 case "$1" in