http in eve alert log

https://github.com/inliniac/suricata/pull/1097, with a small addition (https://github.com/inliniac/suricata/commit/f453fb810f04bb7e8c0e831ad209a9184897cdc7)

Prscript:
- PR build: https://buildbot.openinfosecfoundation.org/builders/inliniac/builds/11
- PR pcaps: https://buildbot.openinfosecfoundation.org/builders/inliniac-pcap/builds/11