Core API: using addAssocDef() inappropriately corrupts the DB

[jri]

In a migration a developer often uses this one to add an assoc def to a type:

dm4.getTopicType("infobits.tree").addAssocDef(
    mf.newAssociationDefinitionModel("dm4.core.aggregation_def",
        "infobits.infobit", "dm4.files.file", "dm4.core.many", "dm4.core.many"));

If the type URI passed to getTopicType() does not match the parent type URI in the newAssociationDefinitionModel() call (2nd argument) the DB gets corrupted:

DB inconsistency: type "infobits.tree" has 3 association definitions but in sequence are 4

The Core should check that condition and reject that addAssocDef() call by throwing an exception.