Keep a minimum number of sync session logs on the client, for future use in stats display.
None === no limit.  adding TODO
Merge pull request #188 from bcipolli/persist_syncsessions

Keep a minimum number of sync session logs on the client, for future use in stats display.
Merge pull request #187 from bcipolli/python26_cleanup

Python26 cleanup
Merge branch 'user_activity_logs' of git://github.com/bcipolli/ka-lite into bcipolli-user_activity_logs
Merge remote-tracking branch 'upstream/develop' into user_logs_syncing
Merge branch 'user_logs_syncing' of github.com:bcipolli/ka-lite into user_logs_syncing