Merge 'Add closing of sensor on KeyboardInterrupt'

See merge request card10/firmware!309

preload/apps/ecg/__init__.py

@@ -384,4 +384,8 @@ def main():
 
 
 if __name__ == "__main__":
-    main()
+    try:
+        main()
+    except KeyboardInterrupt as e:
+        sensor.close()
+        raise e