Create signed recipes during `make refresh`

[jaredlockhart]

Now that we have the handy dandy make refresh command in Normandy, we should auto generate some signed recipes to help quickly recreate the state we expect stage or prod to be in. This will help with debugging and testing locally.

[jaredlockhart]

I was able to create a signed recipe using

from normandy.recipes.tests import RecipeFactory

RecipeFactory(signed=True)

Maybe we can set it up the same way we did with Experimenter and make a management command to make 10 dummy signed recipes and then invoke it in make refresh

[mythmon]

I'd be careful with those factories. RecipeFactory(signed=true), for example, creates a fake signature that is just a hash of the data, not an actual signature. It's useful for tests, because it is simple and verifiable, but it's basically a mock.