resolve warnings generated by rails_erd

[alexdean]

Hey all. When I run rake erd (from the rails-erd gem), i get the following warnings...

Loading application environment...
Loading code in search of Active Record models...
Generating Entity-Relationship Diagram for 20 models...
Warning: Ignoring invalid association :live_build on FrontEndBuilds::App (model FrontEndBuilds::Build exists, but is not included in domain)
Warning: Ignoring invalid association :builds on FrontEndBuilds::App (model FrontEndBuilds::Build exists, but is not included in domain)
Warning: Ignoring invalid association :recent_builds on FrontEndBuilds::App (model FrontEndBuilds::Build exists, but is not included in domain)
Done! Saved diagram to erd.pdf.

I don't think this is actually serious, but it would be nice to have some idea how to quiet this.