certbot renew-hook for tlsa generation

[John Allen]

if anybody is interested I have created a automatic TLSA generator and
installer (bind only for the moment). you can find it here
https://github.com/zzz2002/Certbot-renew-hook

I still have to do the documentation. it can be run as a renew-hook for
letsencrypt (certbot) or standalone.

WARNING it still being worked on, but whats there seems to work. let me
know of any problems, suggestions