Overriding Debug#parent

I am overriding Debug#parent to either return the Debug's parent, or the Debug itself.

The reason I am changing this functionality is so I do not need to do a conditional in the DebugsController#create method when redirecting (Without this change, I would need to check if the Debug that was saved has a parent and redirect to that or redirect to the Debug itself).

Signed-off-by: Brian Bommarito <brian@bbommarito.com>