ts: test tags for flexible/reliable tests filtering

- added functionality to collect memory usage of OpenCL sybsystem
- memory usage of fastMalloc() (disabled by default):
  * It is not accurate sometimes - external memory profiler is required.
- specify common `CV_TEST_TAG_` macros
- added applyTestTag() function
- write memory usage / enabled tags into Google Tests output file (.xml)

modules/core/src/system.cpp

@@ -71,6 +71,8 @@ static bool param_dumpErrors = utils::getConfigurationParameterBool("OPENCV_DUMP
 );
 
 void* allocSingletonBuffer(size_t size) { return fastMalloc(size); }
+void* allocSingletonNewBuffer(size_t size) { return malloc(size); }
+
 
 } // namespace cv