Better config system

[Romern]

On windows paths are difficult to type into the json file, it would be better to use maybe the default configparser from python

[septatrix]

Definitely +1 for using configparser. We should probably add a helper for the conversion as this would be a breaking change. As part of the same step we could make some other semantical breaking changes to the config format (like asking for a password if non is set and having to explicitly enable the keyring mechanism) besides the obvious syntactical ones. Also we may should have a short period where both formats are valid to ease the transition further.