[PVE-User] Change pveproxy to tls1.2

[Dietmar Maurer]

> > We reverted that change, because it breaks IE.
> Oh, that's a pity. :) *going to reenable it manually*
> 
> Thanks for your feedback!
> 
> PS! IF I change Ciphers list from /etc/default/pveproxy, couldn't it be 
> that I can adjust TLS versions and SSL versions there as well?

We plan to update to debian jessie soon, and hopefully the updated libs work
with IE. We
can the re-enable those settings.