Change default naming of FK fields

The current way of naming fields linked to foreign keys is refMyEntityId, but this is not very user friendly. We discussed that with Tomáš and the new way should be MyEntity_Id, for example “Priority_Id” instead of “refPriorityId”.
It is necessary to keep the old way by legacy projects but for new projects the new way will be used. In the future the naming convention may be set up by users in Configuration.