Merge branch 'Clustering'

Conflicts:
	src/clustering/clustering.py
	src/clustering/group.py
	src/scheme/__init__.py
	src/scheme/atomic.py
	src/scheme/blockbase.py
	src/scheme/composite.py
	src/scheme/connection.py
	src/scheme/gcomposite.py
	src/scheme/genericcomposite.py
	src/tests/test_clustering.py
Fix show and add save_representation function.