Fix automatic header file dependency for MatCaffe

Automatic header file dependency was introduced in BVLC#1472, but
not correctly applied to matcaffe. Fix it by moving ./caffe_.d
to build/matlab/+caffe/private/caffe_.d and add it to DEPS

Makefile

@@ -118,7 +118,7 @@ GTEST_OBJ := $(addprefix $(BUILD_DIR)/, ${GTEST_SRC:.cpp=.o})
 EXAMPLE_OBJS := $(addprefix $(BUILD_DIR)/, ${EXAMPLE_SRCS:.cpp=.o})
 # Output files for automatic dependency generation
 DEPS := ${CXX_OBJS:.o=.d} ${CU_OBJS:.o=.d} ${TEST_CXX_OBJS:.o=.d} \
-	${TEST_CU_OBJS:.o=.d}
+	${TEST_CU_OBJS:.o=.d} $(BUILD_DIR)/${MAT$(PROJECT)_SO:.$(MAT_SO_EXT)=.d}
 # tool, example, and test bins
 TOOL_BINS := ${TOOL_OBJS:.o=.bin}
 EXAMPLE_BINS := ${EXAMPLE_OBJS:.o=.bin}
@@ -460,6 +460,9 @@ $(MAT$(PROJECT)_SO): $(MAT$(PROJECT)_SRC) $(STATIC_NAME)
 			CXX="$(CXX)" \
 			CXXFLAGS="\$$CXXFLAGS $(MATLAB_CXXFLAGS)" \
 			CXXLIBS="\$$CXXLIBS $(STATIC_LINK_COMMAND) $(LDFLAGS)" -output $@
+	@ if [ -f "$(PROJECT)_.d" ]; then \
+		mv -f $(PROJECT)_.d $(BUILD_DIR)/${MAT$(PROJECT)_SO:.$(MAT_SO_EXT)=.d}; \
+	fi
 
 runtest: $(TEST_ALL_BIN)
 	$(TOOL_BUILD_DIR)/caffe