adapting to visual studio
LayerViewerGui (base class): Don't allow subclasses to re-use layer instances in setupLayers().
ObjectClassification: Don't re-use layer instances, which isn't allowed by the LayerViewerGui base class.
Fixes #564
PixelClassification: Auto-disable live update if the "Live update" button is auto-disabled.
All applets: Guis implement stopAndCleanup() and unsubscribe from slot notifications on cleanup.
add a button to export object features to a pickle file
change the block channel dimensions
add the filter implementation switch to pixel classification
ObjectClassification: Fixed update of prediction layer colortable so it stays in sync with the label list colors.
PixelClassification: Disable upstream applets when "Live update" mode is active.
Fixes #577
don't own the prediction layer
check if there are features selected
ObjectClassification: fixes #560
DatasetConstraintError: Added a string representation.
OpDataSelection.InvalidDimensionalityError: Added a string representation.
OpParseAnnotations.AnnotationParsingException: Added a string representation.
ilastik.py: Global excepthook in gui-mode uses str(ex) to display exception messages, not ex.message (which is deprecated and doesn't work in all cases).
Merge pull request #594 from burgerdev/issue-560

ObjectClassification: fixes #560
fillmissing: refactoring, pep8 compliance, lazyflow changes
Merge pull request #595 from burgerdev/pr-fillmissing-refactoring

fillmissing: refactoring, pep8 compliance, lazyflow changes