The Plugin now allows external plugins to define types of dataset by:
- extending the generic-dataset-controller.inc and implementing the _managedType() method to return the dataset type.
- the dataset.inc is one example, providing the 'file' default dataset type, this is saved to the new _mksdc_managed_type_key post meta field
Added the extension point 'template' to provide alternative visualizations for datasets, for example depending on the managed type.
Minor improvements and fixes.