core77: drop xen kernel support.

The legacy xen kernel is incompatible to grsecurity and new udev so we are forced to drop the support. We have anounced this step 8 month ago.
http://planet.ipfire.org/post/dropping-support-for-xen-3-x-deprecation-warning
openssl: security update to 1.0.1h.
core78: create emergency update.

all changes planned and build in testing will moved to core79.