Reduction of parameter requirements

The goal was to reduce the parameter requirements :

• All the objects Img<T> used as parameters have been replaced by RandomAccessibleInterval<T> or IterableInterval<T> objects.
• A parameter ImgFactory<T> has been added when the creation of an Img<T> as an output was necessary.
• The class Histogram<T> from package net.imglib2.algorithm.stats has been copied (class HistogramZ) and the constructor parameter Img<T> has been change into IterableInterval<T>.