Log Message:
Changes 1.8.0:
* Various extensions to Local Minima and Maxima (3D algorithms, on-the-fly
  thresholding).
* Added vigra::BucketQueue, vigra::MappedBucketQueue.
* Refactored and extended 2D watershed algorithms (especially
  watershedsRegionGrowing()).
* Added the vigra::Quaternion class.
* Added Unsupervised Decomposition.
* Added mathematical functions (even(), odd(), gamma(), loggamma(), legendre(),
  besselJ(), besselY(), linearSequence(), indexSort(), inversePermutation(),
  applyPermutation(), checksum())
* Implemented wrapper of the FFTW library to support arbitrary dimensional
  Fourier transforms (see fourierTransform() and vigra::FFTWPlan) and FFT-based
  convolution (see convolveFFT() and vigra::FFTWConvolvePlan) and refactored
  vigra::FFTWComplex.
* Added cannyEdgelListThreshold(), cannyEdgelList3x3Threshold().
* Added capability to handle subarrays and anisotropic resolution to
  separableConvolveMultiArray() and related Gaussian filters. Added windowRatio
  parameters to vigra::Kernel1D::initGaussian() and
  vigra::Kernel1D::initGaussianDerivative()
* Added vigra::StridedScanOrderIterator and corresponding
  vigra::MultiArrayView::begin().
* Extended vigra::MultiArrayView. Added vigra::Shape1 ... vigra::Shape5
  convenience typedefs.
* Implemented vigra::multi_math (arithmetic and algebraic functions for
  multi-dimensional arrays).
* Extended the vigra::HDF5File class.
* Improved and documented the Timing macros for runtime measurements.
* Added support for the OpenEXR image format and multi-page TIFF. Improved
  support for the SIF format.
* vigranumpy: added axistags and completly re-implemented VigraArray and the
  conversion between Python and C++ arrays in terms of axistags.
* Minor improvements and bug fixes in the code and documentation.