Change application.js to not pull in all JS in the tree, as the active_admin JS was being complied into the non-admin CSS. active_admin expects active_admin.js to be in /app/assets/javascripts (and only there, no subdirectories).

To fix this, I moved all app-specific JS into an 'app' subdirectory of 'javascripts' and changed application.js to pull everything from that directory (and only that directory).