Audit Log interface, schema, and cassandra implementation

More audit log stuff.

More audit logging work

Audit log tests and docs
Don't use pretty JSON in prod.  Logging single line will make getting it into logstash easier.
Fix lint.
Actually handle indent=False.
Simpler indent=False
in Additional Resources, add suggestion to see GitHub repo
Merge branch 'master' of github.com:rackerlabs/otter into TWrose
in API Operations chapter, standardize major section titles: x.x Groups, Configurations, Policies, etc (not Group Resources etc)
in General API Information chapter, add annotated examples of authentication credientials and service catalog response
Checkpoint supervisor refactor.
in General API Information chapter, add guesses for all regional endpoints
Pass authentication function not authenticator class.
Fix lint.
in General API Information chapter, reformat example of ISO-8601 date/time standard format
in General API Information chapter, standardize title of sample fault
delete unused autoscale-reference.xml: early partial draft, now incorporated into autoscale-devguide.xml
Remove docbook target, and update .gitignore to ignore that directory from now on.
Merge pull request #266 from rackerlabs/no-pretty-json

Don't use pretty JSON in prod.  Logging single line will make getting it...
Change to internal comments instead of Disqus for now.
Flagging these docs as internal

since we're only publishing to docs-internal for now.