Modularize benchmarks subproject

src/benchmarks/CMakeLists.txt

@@ -0,0 +1,20 @@
+file(GLOB RTreeBenchmarkSources
+    *.cpp)
+
+add_executable(rtree-bench
+	EXCLUDE_FROM_ALL
+	${RTreeBenchmarkSources}
+	$<TARGET_OBJECTS:UTIL>)
+
+target_include_directories(rtree-bench
+	PUBLIC
+	${PROJECT_SOURCE_DIR}/unit_tests)
+
+target_link_libraries(rtree-bench
+	${Boost_LIBRARIES}
+	${CMAKE_THREAD_LIBS_INIT}
+	${TBB_LIBRARIES})
+
+add_custom_target(benchmarks
+	DEPENDS
+	rtree-bench)