Add a config test helper

[adamcik]

As we add core config values that are needed for other "unrelated" tests to work we are getting a lot of places that set dummy configs. Ideally we should replace this with a tests.config({...}) which returns a merged config with the defaults we need.

[adamcik]

#1225 adds a bunch of these which should be reverted once this gets fixed.

[RonaldZ]

Was thinking the same thing while working on #1225. I'm on it.

[adamcik]

Added you to the repo as a collaborator so you can take bugs etc :-)