Logging strategy...

Actions emits one log message at 'notice' level that describes
the overally goal of the action.

Repository emits one or two log messages at 'info' level for each major
operation.  Minor operations logged at 'debug' level.

Database, cache, & collaborators always log at 'debug' level.

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What is the purpose of the log???

* To record who made what modifications to the repository and when

* To help debug and diagnose operational problems

* To record operational events
