ssh v8

Re-enable SSH protocol detection, parser and keywords. Also add simple SSH JSON logging. It logs proto and software version for both client and server.

https://redmine.openinfosecfoundation.org/issues/1119

Prscript:
- PR build: https://buildbot.suricata-ids.org/builders/inliniac/builds/213
- PR pcaps: https://buildbot.suricata-ids.org/builders/inliniac-pcap/builds/133

Rebased version of https://github.com/inliniac/suricata/pull/865