Lifespan of auth_tokens

Currently our auth_tokens have a lifespan of 2 weeks, which is unecessarily long and opens the door for potential abusive usage of features like notifications. To address this, we are going to start reducing the lifespan by a day each day for the next 2 weeks until it is 1 day.

We do expect to add support for authentication via API Key + a secret key per application, to allow for things like periodic email newsletters. No ETA on that support yet, but we do know it's a valuable feature that you'll be looking out for in the future.