JSON-able classifiers
- Cluster classifiers can now be saved as JSON files.
- Added attributes 'spechomo_version' and 'spechomo_versionalias' to ClusterLearner.
Signed-off-by: Daniel Scheffler danschef@gfz-potsdam.de
Signed-off-by: Daniel Scheffler danschef@gfz-potsdam.de