Changed error print into logger.warning

mdevaluate/correlation.py

@@ -162,7 +162,7 @@ def shifted_correlation(function, frames, selector=None, segments=10,
                                            selector=selector), 
                                    start_frames))
     except Exception:
-        print("Something went wrong!")
+        logger.warning("Something went wrong while calculating the shifted correlation!")
     finally:
         pool.terminate()
         pool.restart()