logging: first pass at logstash-forwarder

This is a first pass at shifting to use [Logstash-Forwarder](https://github.com/elasticsearch/logstash-forwarder) for log shipping. This is an alternative to the previous rsyslog attempts after numerous discussions on tradeoffs. 

Known Issues which will be fixed here:
 - [x] Hardcoded receiving endpoint
 - [x] Global log config instead of per-service
 - [x] Missing cleanup from prior rsyslog attempts

Known Issues which will be fixed in other PRs:
 - [ ] Following system log files
 - [ ] Own certificate instead of shared/common
Seems most of the logging configs are single tasks, is there a strong reason to break that into an include file, vs just putting the task in the main.yml directly (and including the tags: key)?