update ANN to latest version (1.1.2), released under the LGPL

CREDITS.txt

contrib/ANN/Copyright.txt

contrib/ANN/License.txt

contrib/ANN/README.txt

contrib/ANN/include/ANN/ANN.h

contrib/ANN/include/ANN/ANNperf.h

contrib/ANN/include/ANN/ANNx.h

contrib/ANN/src/ANN.cpp

contrib/ANN/src/kd_dump.cpp

contrib/ANN/src/kd_fix_rad_search.cpp

contrib/ANN/src/kd_fix_rad_search.h

contrib/ANN/src/kd_pr_search.cpp

contrib/ANN/src/kd_search.cpp

contrib/ANN/src/kd_util.cpp

contrib/ANN/src/perf.cpp

contrib/ANN/src/pr_queue.h

contrib/ANN/src/pr_queue_k.h