quickly corrected the previous refactoring of features2d: moved from set(SOME_PROP, val) to setSomeProp(val)

OpenCV with the refactored features2d compiles! contrib is broken for now; the tests are not tried yet

OpenCV with the refactored features2d compiles! contrib is broken for now; the tests are not tried yet

IPP can be switched on and off on runtime;

Optional implementation collector was added (switched off by default in CMake). Gathers data of implementation used in functions and report this info through performance TS;

TS modifications for implementations control;

Implemented as a new optional parameter for
the constructor of the ORB detector. The
change of this parameter has been included
in the orb unit test.

Added the defaultNorm() method to the DescriptorExtractor class. This method returns the default norm type for each descriptor type. The tests and C/C++ samples were updated to get the norm type directly from the DescriptorExtractor inherited classes.

This was reported in feature report #2182 (http://code.opencv.org/issues/2182). It will make it possible to get the norm type usually applied matching method for each descriptor, instead of passing it manually.

(master branch was fixed before, no need to merge this to master!)
- disable openexr (numerous undefined std::min & std::max)
- workaround for two compilator bugs

Made all STL usages explicit to be able automatically find all usages of
particular class or function.

added initModule_features2d(). Possibly solved problem when the linker excludes seemingly unused detectors/descriptors.

Made small change which fixes the situation, when ORB does not find any descriptors on an image. Earlier ORB::operator() crashed in this case, since rowRange method was called for an empty matrix.