User logs syncing

This pull request is a continuation of #182 and #66.  Here, I extend the prior logic to only sync fields across machines that don't have a version mismatch to sync **models** across fields that don't have a version mismatch.

This allows me to sync UserLogSummaries across machines that have this model object--the real purpose of this pull request.

Code review for this will need to wait until #182 (and its dependencies) is merged.