Send logs in logstasher schema v1 format and rotate logs

Send logs in this format:  https://logstash.jira.com/browse/LOGSTASH-675

Also, rotate the logstash_production.log file.  10 files, 250MB max.  
I think it's good to avoid hard-coding in rotation. Many use `logrotate` or similar and would like to keep using their existing mechanism for log rotation. Also, I remember reading about multi-process cases where this could cause bugs.

Keeping it off by default (with an option to enable) is probably a good idea.