Fixed NPE due to a not set rowkey if a series of images have been read.
Different naming of the temporary files downloaded, if image is openend from an url:
+ whole url + an extracted image suffix (e.g. tif) since need by some scifio formats to identify the right format
Removed unused method
Algorithms-GPL: New Lib
Removed redundant FFTConvolution. Using ImgLib2 Implementation now
Adapted Convolvers to use ExecutionService

By far, this is not a beautiful solution. But as we plan to use ImageJ2 Ops
in the future, we don't care. It works!
fixed executorservice in SobelNodeFactory
disabled plane-wise parallelization at sobel
Wrapping Img not ImgPlus as subsetview
Updated ImgLib2-Core Library
Labeling can now be virtually extended, even if num dims differs
Added LabelingExt0 and LabelingViewExt0

Generic Labeling Serialization. Should just be called in special cases,
e.g. when a LabelingView is serialized.
Removed debug output from LabelingExt0
LabelingExt0:improved java doc (a bit)
ImgPlusCell: getImgPlusCopy() should copy _all_ metadata
removed deprecated code
code-cleanup
ResizerNodeFactory: fixed aiob exception
Adding DontSaveStart and DontSaveEnd
Moving Slice Iterator to util package