ilastik/applets/nanshe/preprocessing/opNanshePreprocessData.py: Mark cache as dirty if the last element in the pipeline is removed.
ilastik/applets/nanshe/preprocessing/opNanshePreprocessData.py: Remove checks of connected slots for OpNanshePreprocessData.
ilastik/applets/nanshe/preprocessing/opNanshePreprocessData.py: Remove checks of connected slots for OpNanshePreprocessDataCached.