added relational operators for autodiff::DualVector
support automatic differentiation of BSplines
fixed macro VIGRA_DUALVECTOR_RELATIONAL_OPERATORS
minor documentation fixes
changed shared library version format (patch by Hans Meine)
fixed cmake warning
remove now-unused cmake var. definition

(see initial patch in issue #163)
silenced new gcc warnings
compatibility fixes for Visual Studio 2013
cmake: improved search for boost libraries
fixed typo in tutorial
removed invalid using declaration
removed debug output in labelvolume.hxx
ignore potential python3 installations
Merge pull request #165 from burgerdev/python-findpackage

ignore potential python3 installations (handle as missing vigranumpy dependency)
added integral_image and test
Disable VIGRANumPy by default with GNU c++ < 4.4 on MacOSX

This developer's machine is basically stuck with GNU C++ 4.2 as that is
the last XCode version available for MacOSX 10.6 (and the machine is not
upgradeable).

Rather than leaving other developers with the same problem puzzled about a
weird and long compile error, let's be nice and just disable VIGRANumPy in
that case.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Merge pull request #166 from dscho/handle-gcc-4.2

Disable VIGRANumPy by default with GNU c++ < 4.4 on MacOSX
added MultiArrayView::multiband() convenience function and test
refactored and generalized integral image code