message: CMake: Prevent conflicts in the test runner when liblcf is added as a subdirectory.
  test_runner target is changed to test_runner_lcf and check target is only created when not available already, otherwise it attaches itself to check
diff: @@ -329,10 +329,15 @@ endif()
  # tests
  file(GLOB TEST_FILES ${CMAKE_CURRENT_SOURCE_DIR}/tests/*.cpp)
  -add_executable(test_runner EXCLUDE_FROM_ALL ${TEST_FILES})
  -target_link_libraries(test_runner lcf)
  -add_custom_target(check COMMAND ${PROJECT_BINARY_DIR}/test_runner)
  -add_dependencies(check test_runner)
  +add_executable(test_runner_lcf EXCLUDE_FROM_ALL ${TEST_FILES})
  +set_target_properties(test_runner_lcf PROPERTIES OUTPUT_NAME "test_runner")
  +target_link_libraries(test_runner_lcf lcf)
  +add_custom_target(check_lcf COMMAND test_runner_lcf)
  +if(NOT TARGET check)
  + add_custom_target(check)
  +endif()
  +add_dependencies(check_lcf test_runner_lcf)
  +add_dependencies(check check_lcf)
  # benchmarks
  file(GLOB BENCH_FILES ${CMAKE_CURRENT_SOURCE_DIR}/bench/*.cpp)
  