Fixed import error on Windows.

Conflicts:
	src/cpp/flann/general.h

- implement the same for radius (no size limit)
- implement a radius/k NN set

Reformated source code to fix indentation inconsistencies. Added script for automatic code indentation.

The hiererchical clustering index is similar to the k-means index, but it only requires a metrix distance to be defined between different feature points. It has good performance for binary features (such as BRIEF visual features).