Fix regression introduced in odbc/mnesia merge
Disable SSL 2.0 in TLS driver

SSL 2.0 is not used anywhere as it has security problems. Disable it
unconditionally both in server and client mode. This does _not_
disable support for SSL 2.0 compatible client hello which still will
be accepted in the server mode.
Disable old and unsecure ciphers in TLS driver

Disable:
- export ciphers - broken by design, 40 and 56 bit encryption
- low encryption ciphers - 56 and 64 bit encryption
- SSLv2 ciphers - some ciphers using MD5 MAC
Enable ECDHE key exchange in TSL driver
Enable DHE key exchange in TLS driver
Detect OpenSSL version at runtime, not at compile time
Send announce Message stanzas as Headline type instead of Normal
On shutdown, first stop listeners, then modules (thanks to Vishal Xica)(EJAB-1566)
Added clause so ejabberdctl number of arguments error report works with R15
Add SCRAM and remove MD5 support to ejabberd commands auth verification
Log IP address when auth attempt fails (thanks to Zach Calvert)
Document in the guide the db_type modules option (EJAB-1560)
New Hebrew translation (thanks to Isratine Citizen)
Fixed mod_offline:store_offline_msg argument (EJAB-1581)
Make terms serialization faster
Copy, fix and document export2odbc command from mod_admin_extra.erl
Fix broken JPEG photo (EJAB-1526)
Merge pull request #37 from rraptorr/tls

TLS driver impovements
Added command to list all the vhosts registered in an ejabberd node
Fixed signedness issue in tls_drv GET_DESCRYPTED_INPUT (EJAB-1591)