Added unit tests for FHOG feature extractor.

dlib/test/CMakeLists.txt

@@ -45,6 +45,7 @@ set (tests
    entropy_encoder_model.cpp
    example_args.cpp
    fft.cpp
+   fhog.cpp
    filtering.cpp
    find_max_factor_graph_nmplp.cpp
    find_max_factor_graph_viterbi.cpp

dlib/test/makefile

@@ -60,6 +60,7 @@ SRC += empirical_kernel_map.cpp
 SRC += entropy_coder.cpp
 SRC += entropy_encoder_model.cpp
 SRC += fft.cpp
+SRC += fhog.cpp
 SRC += filtering.cpp
 SRC += find_max_factor_graph_nmplp.cpp
 SRC += find_max_factor_graph_viterbi.cpp