Move app.yaml to app.yaml.template and add app.yaml to svn:ignore in trunk/app. Each Google App Engine instance needs its own "application:" ID, and this should *not* be committed into the SoC SVN repository in trunk/app. (Individual deployment branches *will* have app.yaml files with Google App Engine application IDs in them, just not trunk/app.)

from django.core.management.base import NoArgsCommand

class Command(NoArgsCommand):
    help = "Validates all installed models."

    requires_model_validation = False

    def handle_noargs(self, **options):
        self.validate(display_num_errors=True)