Specify sentry-raven version: 0.10.1

So anyone working on this is going to want to be sure that they **unset sentry_dsn:** in their local version of api_keys.yml (or, alternatively, put in your desired sentry_dsn into api_keys.yml). Basically, we don't want to send local errors to a Sentry account that's supposed to be monitoring a non-local environment.