1.1.1:
   * (09/10/2007) Modified Makefiles to create a static library out of
        individual object files
   * (01/08/2009) Updated VC projects in Windows release to VC 2005 (VC
        2003 versions still available as .old files)
 In kdtree.c/kdtree.h:
   * (12/14/2006) [API] Removed kd_root structure and kd_root_node(); 
        now uses only kd_node
   * (12/14/2006) Fixed kdtree_release() to get rid of big memory leak
   * (12/14/2006) [API] Changed kdtree_release() prototype
   * (12/14/2006) Added bbf_data structure to avoid potential data loss 
        in bbf search
   * (01/19/2007) Fixed memory leak in kdtree_build()
   * (03/30/2007) Fixed pq insertion bug in explore_to_leaf()
 In sift.c:
   * (12/14/2006) Fixed significant bug in interp_hist_entry()
   * (12/14/2006) Fixed memory leak stemming from scale_space_extrema()
   * (01/19/2007) Fixed memory leak in calc_feature_oris()
   * (09/10/2007) Removed unused variables in convert_to_gray32() and
        scale_space_extrema()
   * (11/08/2007) Changed RGB2GRAY flag to BGR2GRAY in convert_to_gray32()
        to conform to OpenCV image storage conventions
   * (01/08/2009) Fixed memory leak in convert_to_gray32()
 In xform.c
   * (09/10/2007) Fixed potential overflow error in calc_min_inliers()
 In imgfeatures.c/imgfeatures.h
   * (09/13/2007) [API] Renamed 'class' field of struct feature to
        'category' for compliance with C++ language (class is a keyword)
