cmake custom target: test-eer

rt/imageio/CMakeLists.txt

 add_executable(test_eer test_eer.cpp)
 target_link_libraries(test_eer EM2)
 add_test(test-eer test_eer)
+
+add_custom_target(test-eer
+        COMMAND ${CMAKE_CTEST_COMMAND} -V -C Release -R test-eer
+        DEPENDS test_eer
+        )