[Merge] lp:~ken-vandine/history-service/model_tweaks into lp:history-service

[Renato Araujo Oliveira Filho]

I have a similar MR for thead model: https://code.launchpad.net/~renatofilho/history-service/threadmodel-with-count/+merge/223634
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https://code.launchpad.net/~ken-vandine/history-service/model_tweaks/+merge/223554
Your team Ubuntu Phablet Team is requested to review the proposed merge of lp:~ken-vandine/history-service/model_tweaks into lp:history-service.