ConversionJpaDaoSupport attempts to persist/delete detached entities

[javier-godoy]

In most cases convertTo(entity) will return a detached entity, thus persist/delete will fail.

https://github.com/AppJars/commons-backend/blob/366e60e10a4db58e280bf7723d4421778aeeb86d/commons-data-impl/src/main/java/com/appjars/saturn/dao/jpa/ConversionJpaDaoSupport.java#L73-L82