* added LUT preservation on some sequence operation (extract frame /
slice..)
* the histogram "auto bounds" parameter is now preserved.
* added MainInterface.getActiveLUT() for fast retrieving of current
viewer's LUT.
* added new methods in LUT and LUTChannel to copy colormap and scaler
objects.
* RectanglexD: fixed some typos in contains() and intersects() methods
* ROIxDStack: fixed rounding error in contains(..)and intersects()
methods