Fix JSON syntax errors in default config, close config file after loading and fix issue #55

Fixed a couple of issues related to a first time run of the RedisLive.

* The default config file wasn't being parsed properly and the SQLite settings needed to be a dictionary with a `{"path": "path to db"}`.
* The settings file is also not being closed when loading the settings.
* Fixed setting default password to None (issue #55) when a server's settings didn't have the `password` field set.