Enc doesn't support AEAD ciphers.
(cherry picked from commit 09184dddead165901700b31eb39d540ba30f93c5)
Moved note about lack of support for AEAD modes out of BUGS section to SUPPORTED CIPHERS section (bug has been fixed, but still no support for AEAD)
Unit/regression test for TLS heartbeats.

Regression test against CVE-2014-0160 (Heartbleed).

More info: http://mike-bland.com/tags/heartbleed.html

(based on commit 35cb55988b75573105eefd00d27d0138eebe40b1)