The ErpEntityInterface interface was changed in a previous commit.
We decided to declare this as a breaking change to create a version 3. with this commit pgpstan level 0 and 1 are also done.

BREAKING CHANGE: ErpEntityInterface extended

feat: manufacturers -> setting for default manufacturer group; auto-create manufacturer group if none exists; read from product fields only if products is installed

feat: integrated global erp timestamp and date formats - all ERP modules should use these date / timestamp settings