- Take into account that `BaseException` may also raise `ValueError` if unable to decode JSON
- New `get_or_none` method for managers that returns `None` if not found, instead of raising an exception
- Allow collection endpoints to be defined without trailing slashes and make sure resource endpoints always have one
- `expand` option for resource-type fields, so that they will be represented as a dictionary with an `id` field instead of just the ID.