certmanager: if OpenSSL version >= 1.0.1, also remove all DES and Triple DES ciphers.
certmanager: following the previous commit also disable SSLv3.
mod_c2s: remove legacy ssl listener,
- It should be firmly discouraged using it.
- And it may cause a mess since with higher OpenSSL versions we enforce the
no_sslv3 flag now, and older clients may not like it, obviously.
Set version file to 3.0, additional commits may come before the actual release.