When using self referential relationships in boolean expressions, the exists clause incorrectly uses the table names to qualify columns which will be the same for parent table and the child table. This is now fixed by generating unique aliases as we traverse down the relationships.
* don't allow fkey based relations from/to a table that isn't tracked, fix#185
Check if remote table exist in metadata when creating foreign-key
based object relationship.
* add tests for adding object relation using fkey if remote table is untracked
