Add compile errors for properties of relations in Where queries

Let's say you have a Book class with an author property of type Author. I would like the query

Book.where { author.nam =~ "Stephen%" }

to fail with a compilation error (the property should be name). The main reason for this request is that I think users will find it very strange that authr.name is a compilation error but the above is not.

You can use the project attached to GRAILS-8344 for testing. Just edit the query in BookController.groovy.