Auditd statsd integration

[Steve Grubb]

Hello,

I have recently checked in to the audit tree 2 experimental plugins. You can 
enable them by passing --enable-experimental to configure. One of the new 
plugins is aimed at providing audit metrics to a statsd server. The idea 
being that you can use this to relay the metrics to influxdb, prometheus or 
some other collector. Then you can use Grafana to visualize and alert.

Currently, it supports the following metrics:

kernel.audit.lost
kernel.audit.backlog
auditd.free_space
auditd.plugin_current_depth
auditd.plugin_max_depth
audit_events.total_count
audit_events.total_failed
audit_events.avc_count
audit_events.fanotify_count
audit_events.logins_failed
audit_events.logins_success
audit_events.anomaly_count
audit_events.response_count

I'd be interested in hearing if this would be useful. And if these are the 
right metrics that people are interested in. Should something else be 
measured? Should an example Grafana dashboard be included?

Let me know what you think.

-Steve