Modify a comment about Xeus cling not able to run a cell - it works with some...

Modify a comment about Xeus cling not able to run a cell - it works with some versions (it didn't on last that was working in macOS but does in the one in the Docker image).

1-ProceduralProgramming/6b-TP.ipynb

@@ -345,5 +345,5 @@
   }
  },
  "nbformat": 4,
- "nbformat_minor": 2
+ "nbformat_minor": 4
 }

2-ObjectProgramming/7-polymorphism.ipynb

@@ -912,7 +912,7 @@
    "source": [
     "You may in fact explicitly tells the `c` pointer needs to be interpreted as a `PolymorphicThermicCar`:\n",
     "\n",
-    "**Xeus-cling issue:** Here cling doesn't manage to run it but it is accepted rightfully by a full-fledged compiler (see for instance [@Coliru](http://coliru.stacked-crooked.com/a/22fff15d28c93a17)):"
+    "**Xeus-cling issue:** Here cling may not be able to run it (depends on the version used) but it is accepted rightfully by a full-fledged compiler (see for instance [@Coliru](http://coliru.stacked-crooked.com/a/22fff15d28c93a17)):"
    ]
   },
   {