* `widgets.Select2Mixin.__init__` now accepts `select2_options` kwarg to override its `options` settings. Previously `attrs` were being used for this too. This means backward compatibility has been broken here. `attrs` will no longer override `options` values. **The major release version has been changed to 3, because of this backward incompatible change.**
* Mostly major bug fixes in code and design. The changes were many, raising the possibility of backward incompatibility. However, the backward incompatibility would be subtle.
* Auto fields (sub-classes of AutoViewFieldMixin) now accepts `auto_id` parameter. This can be used to provide custom id for the field. The default is 'module.field_class_name'. Ideally only the first instance of an auto field is registered. This parameter can be used to force registration of additional instances by passing a unique value.