Rewrite PrimaryEntityRelationCreate to be more concrete

The check is used to create OS_WFENTRY records for an issue. We need to:

1. rewrite the check and rename the class to be more concrete and less confusing
2. rewrite the check to use a database join to find all the problem issues
3. change the check so that it also looks at the current step record, as without the current step record the issue cannot progress through workflow
4. ensure the check does not assume that the issue uses the default workflow
5. javadoc the class

Note that we already have an Integrity Check that checks the validity of OS_CURRENTSTEP records. The check is called WorkflowCurrentStepCheck. I guess the best thing to do is to combine PrimaryEntityRelationCreate with WorkflowCurrentStepCheck to ensure that the whole integrity is checked.