Add loigstash formatted JSON Gunicorn logs
Add testing logstash output
Add logshipper for json logs in /var/log

This would include gunicorn logs.
Change json log names to log.json (not json.log)
Add a tag filter to example logstash output
Merge branch 'master' into logstash-backdrop-clean

Conflicts:
	hieradata/role-frontend-app.yaml
Remove title tag from pp app logshippers

These are now added directly in the logs.
Merge pull request #89 from alphagov/logstash-backdrop-clean

Logstash backdrop clean